This topic a meaty one with plenty of learnt facts and calculations to build on the facts. You must write notes to help you remember the key points. Also try out the virtual links and further reading. However, don’t get too carried away with all the music stuff which can go pretty deep.
In the video I explain the polarisation of waves (including the polarisation of light) for A Level Physics.
Only transverse waves can be polarised, this video explains why. It also shows ...why sunglasses are known as 'polaroids' and how you can test this yourself on a sunny day.
MY YOUTUBE CHANNEL Your support in watching this video has been invaluable! To contribute towards the free videos on YouTube, make a small donation at: ► https://www.paypal.me/physicsonline
In the video I explain the polarisation of waves (including the [...]
In the video I explain the polarisation of waves (including the polarisation of light) for A Level Physics.
Only transverse waves can be polarised, this video explains why. It also shows ...why sunglasses are known as 'polaroids' and how you can test this yourself on a sunny day.
MY YOUTUBE CHANNEL Your support in watching this video has been invaluable! To contribute towards the free videos on YouTube, make a small donation at: ► https://www.paypal.me/physicsonline
MY YOUTUBE CHANNEL Your support in watching this video has been invaluable! To contribute towards the free videos on YouTube, make a small donation at: ► https://www.paypal.me/physicsonline
In this video I explain two more properties of waves: amplitude and [...]
In this video I explain two more properties of waves: amplitude and intensity, for A Level Physics.
This catches lots of people out. If you double the amplitude of a wave ...you give it four times as much energy, this leads on to the relationship between amplitude and intensity of a wave.
Thanks for watching,
Lewis
This video is recommended for anyone studying A Level Physics in the following exam boards: AQA CIE Edexcel Edexcel IAL Eduqas IB OCR A OCR B WJEC
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This is a typical quick classical Physics demo of a slinky to show [...]
This is a typical quick classical Physics demo of a slinky to show longitudinal and transverse waves. I have put a scale of 0.5m on the wavelength so you can ...work out a whole wavelength. Also you have a small amplitude scale to show the energy of the wave.
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Standing Waves Demo Chladni Plate
Great idea to show a standing wave for AS Physics. This one uses an AC [...]
Great idea to show a standing wave for AS Physics. This one uses an AC signal and transformer with magnet.
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AC Standing waves on wire. As Physics Prac
This experiment is all about how a wave can be created by passing an AC [...]
This experiment is all about how a wave can be created by passing an AC current through a wire. If the standing wave is only 1/2 of a wavelength you ...can calculate the mass per unit length of the wire.
Clearly this will vary depending on the thickness of the wire used!
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SHM and Circular motion with Phase change
Very cool SHM experiment. Watch to the end to find out the length of the [...]
Very cool SHM experiment. Watch to the end to find out the length of the pendulum. Use the time on the video to compare.
If you work out the cycle time ...from 1min to 1 min 14s. The ball spins around 10 times. This gives a period T = 1.4s
The string is 0.43cm long which gives a theoretical period time T = 1.32s
Interestingly if you work out the expected length to match the pendulum is should be 48.7cm
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Ripple Tank and Waves
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Ealing Film-Loops 80-234 - Refraction of Waves in a Ripple Tank
Ealing Film-Loops 80-234 - Refraction of Waves in a Ripple Tank This [...]
Ealing Film-Loops 80-234 - Refraction of Waves in a Ripple Tank
This film-loop was recovered mid-2016 from Missouri S&T's surplus warehouse and played on a Technicolor 810 instant movie projector designed ...for such 8mm film-loop cartridges. For images of the film-loop cartridge and the descriptive text on the box it came in, please wait until the end of the video. Presented for educational or informational purposes only, for those interested science, pedagogy, bygone educational technology, archival films, ephemeral films, or educational films.
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Ripple Tank 06 Angled Refraction
See all 33 of the ripple tank / 2D wave tank videos linked below... Ripple [...]
See all 33 of the ripple tank / 2D wave tank videos linked below...
Demonstration of standing waves on a string. How the standing waves are [...]
Demonstration of standing waves on a string. How the standing waves are generated, harmonics and more is explained here. See my next video for the explanation: Standing Waves ...Part II: Explanation @James Dann for ck12.org CC-BY-NC-SA
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Standing Waves Part II: Explanation
The derivation for the harmonic frequencies of standing waves on a string [...]
The derivation for the harmonic frequencies of standing waves on a string attached at both ends. By James Dann for ck12.org CC-BY-NC-SA
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How to Read an Oscilloscope - GCSE and A Level Physics
This video explains how to read an oscilloscope. Oscilloscopes are often [...]
This video explains how to read an oscilloscope. Oscilloscopes are often quite old and can be tricky to decipher. However it's not as bad as you think!
Oscilloscopes essentially displays a ...graph that changes in real time. The y-axis is potential difference (voltage) and the x-axis is time. An alternating current source will produce a sinusoidal wave signal on an oscilloscope whereas a direct current will produce a flat line.
For an alternating current source, the distance between two peaks is the time period of the wave, not the wavelength. The time base and the voltage scale of the oscilloscope can be altered in order to see the waveform more clearly.
Thanks for watching,
Lewis
This video is not specifically relevant but recommended for GCSE Physics 9-1 in the following exam boards: AQA (including Trilogy) Edexcel WJEC
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AQA unit 1 past paper question on oscilloscopes. Including a question on [...]
AQA unit 1 past paper question on oscilloscopes. Including a question on timebase and frequency.
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Cathode Ray Oscilloscope - IGCSE and A level Physics
A brief video that explains how the CRO works and how you can use it to [...]
A brief video that explains how the CRO works and how you can use it to work out the frequency and time-period of a wave.
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Chaladni Plate Standing Waves
This is a simple video to show how vibrations from a signal generator make [...]
This is a simple video to show how vibrations from a signal generator make a plate oscillate or move up and down. However, there are places there there is a ...large amplitude and places where the amplitude is zero. This is called a "standing wave" like you would see on a string. This causes the semolina grains to either move a lot or not at all, at the nodus (knot) which you cannot see on the plate!
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Non Newtonian liquid in 1/8 speed
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Non Newtonian fluid Part IV
This is a simple exp using 12.5g of Cornstarch / 10ml of water + some drops [...]
This is a simple exp using 12.5g of Cornstarch / 10ml of water + some drops of food colouring. Place clingflim over the speaker (unless you want ruin it) then ...apply frequency. I used a Lascels generator on max amplitude and a large speaker from Maplin labelled as 10W 8 Ohms TR-150F-R about 15cm diameter. The frequency that things start to really happen is about 36Hz. Try spooning the liquid away from the central dome as shown in the last video of the series.
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Non Newtonian fluid Part III
This is a simple exp using 12.5g of Cornstarch / 10ml of water + some drops [...]
This is a simple exp using 12.5g of Cornstarch / 10ml of water + some drops of food colouring. Place clingflim over the speaker (unless you want ruin it) then ...apply frequency. I used a Lascels generator on max amplitude and a large speaker from Maplin labelled as 10W 8 Ohms TR-150F-R about 15cm diameter. The frequency that things start to really happen is about 36Hz. Try spooning the liquid away from the central dome as shown in the last video of the series.
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Non Newtonian fluid Part II
This is a simple exp using 12.5g of Cornstarch / 10ml of water + some drops [...]
This is a simple exp using 12.5g of Cornstarch / 10ml of water + some drops of food colouring. Place clingflim over the speaker (unless you want ruin it) then ...apply frequency. I used a Lascels generator on max amplitude and a large speaker from Maplin labelled as 10W 8 Ohms TR-150F-R about 15cm diameter. The frequency that things start to really happen is about 36Hz. Try spooning the liquid away from the central dome as shown in the last video of the series.
This section has some quite tricky concepts and really you need to look at the animations and play with the settings to get a feel for what happens to x when I change y etc.. You also need to learn the key diagrams as this will help your explanations. Finally look carefully at the derivations as they also will help you explain the tricky stuff.
Amazing Refraction Magic Trick - The Appearing Beaker
Works on refraction and refractive index being matched.
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Amazing Refraction Magic Trick - The Appearing Beaker
Works on refraction and refractive index being matched.
Works on refraction and refractive index being matched.
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Laser Refraction of Light
This demo shows how you refract light by passing into a denser medium i.e. [...]
This demo shows how you refract light by passing into a denser medium i.e. water. The light slows down so as c is lower than the speed of light the ...wavelength changes (reduces) and it interacts with the medium differently.
Refraction = slowing or speeding up of waves in another medium.
Change of angle can happen when the light enters at an angle which is not at 90 degrees to the normal.
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Refraction and Reflection of Laser Light
This is a simple video to show the principle of the refraction of light and [...]
This is a simple video to show the principle of the refraction of light and also the reflection of light using laser monochromatic light. You can clearly see that the ...light changes direction inside the prism or slows down. This is the idea of "refraction". It turns in towards the normal then away as it exits. The pathway is a constant refraction as the density is even throughout. This is not always the case for example in water the pressure changes cause curved refraction, as it the same effect with seismic waves travelling through the Earth. Interesting as well to see something which students often miss as the reflected ray on the surface of the block or the TIR or totally internally reflected rays from the internal surface of the prism.
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Reflection and Refraction
This movie shows refraction, reflection, TIR with prisms.
This movie shows refraction, reflection, TIR with prisms.
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Dispersion of Laser light
Amazing fun, with lasers
Amazing fun, with lasers
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Neon Spectral Images AS AQA Physics
Spectral lines shown on a spectroscope from a neon geissler tube. This is a [...]
Spectral lines shown on a spectroscope from a neon geissler tube. This is a great quantum effect!
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Spectral Absorption (for A-Level Physics)
When the energy gap between two molecular energy levels is exactly the same [...]
When the energy gap between two molecular energy levels is exactly the same as the photon energy of an incident beam of light, some of the incident light will be ...removed from the beam. On the single-molecule level, the energy of an absorbed photon drives an absorption transition, a nearly instantaneous process that causes the molecule to jump from its ground state to an excited state. Accordingly, the intensity of the light that is transmitted through a solution can be used to determine how many molecules are present in the solution per unit volume.
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Refraction of Light - Introduction | Don't Memorise
What is Refraction of Light? Is Reflection of Light different from [...]
What is Refraction of Light? Is Reflection of Light different from Refraction of Light? Watch this video to know more!
Total Internal Reflection and Critical Angle - A Level Physics
This video introduces and explains total internal reflection and its [...]
This video introduces and explains total internal reflection and its relationship with the critical angle for A Level Physics.
Total internal reflection occurs when light reflects off of the boundary between ...two mediums. Where light gets refracted such that the angle of refraction is greater than the angle of incidence, at some angle, the light will be refracted at an angle of 90 degrees and is reflected instead. The smallest angle of incidence that this occurs at is called the critical angle.
Thanks for watching,
Lewis
This video is recommended for anyone studying A Level Physics in the following exam boards: AQA CIE Edexcel Edexcel IAL Eduqas IB OCR A OCR B WJEC
_____________________________________
MY PHYSICS WEBSITES Find even more videos organised by exam board and topic at:
MY YOUTUBE CHANNEL Your support in watching this video has been invaluable! To contribute towards the free videos on YouTube, make a small donation at: ► https://www.paypal.me/physicsonline
This video explains how optical fibres (or optical fibers if you're [...]
This video explains how optical fibres (or optical fibers if you're American) work for A Level Physics.
Optical fibres use total internal reflection in order to send information. A light signal ...is sent down an optical fibre which can be received quite a distance away. The signal isn't perfect because different light rays travel different distances - this is called modal dispersion. The signal is put through a filter in order to get the original signal back out.
Thanks for watching,
Lewis
This video is recommended for anyone studying A Level Physics in the following exam boards: AQA CIE Edexcel (don't need to know details) Edexcel IAL Eduqas IB OCR A OCR B WJEC
_____________________________________
MY PHYSICS WEBSITES Find even more videos organised by exam board and topic at:
MY YOUTUBE CHANNEL Your support in watching this video has been invaluable! To contribute towards the free videos on YouTube, make a small donation at: ► https://www.paypal.me/physicsonline
This video introduces and explains Young's double slit experiment for A [...]
This video introduces and explains Young's double slit experiment for A Level Physics.
Everyone loves lasers in Physics. Young's double slit experiment uses the constructive interference and destructive interference of light ...from a laser to calculate and measure the wavelength of light. We need the separation of the slits, distance to the screen and separation of the light and dark fringes. You can do this practical without a laser as well.
Thanks for watching,
Lewis
This video is recommended for anyone studying A Level Physics in the following exam boards: AQA CIE Edexcel Edexcel IAL Eduqas IB OCR A OCR B WJEC
_____________________________________
MY PHYSICS WEBSITES Find even more videos organised by exam board and topic at:
MY YOUTUBE CHANNEL Your support in watching this video has been invaluable! To contribute towards the free videos on YouTube, make a small donation at: ► https://www.paypal.me/physicsonline
The double-slit experiment is a classic experiment that is frequently [...]
The double-slit experiment is a classic experiment that is frequently referred to when describing quantum phenomena, so we definitely have to go over it a little bit. What happens when ...you pass a beam of light through a screen with two slits? What about when you send electrons through there? Or just one electron? It's crazy stuff! Check it out.
Quantum physics is the study of the interaction of atoms and the microscopic universe. Quantum Physics gave us TV ...(the image is formed by electrons being shot at a layer of phosphorous on the inside of the screen.) Quantum also gave us microwave ovens, lasers, cell phones, nuclear energy, and the atom bomb.
In the early days Quantum researchers did various experiments on electrons, or the tiny particles that seem to fly around the nucleus of an atom and of which everything in our present existence is made. The results of these experiments caused the world of physics to question many of its laws, and even had Einstein losing it over what it all meant. Neils Bohr, Wolfgang Pauli, Werner Heisenberg, John Bell, and Erwin Schrodinger who made achievements in Quantum physics were all given Nobel Prizes. Unless Nobel Prizes are given for myths or to idiots, the experiments listed below are definitely worth our contemplation.
a) The most important experiment was known as the Double Slit Experiment.
This experiment was simply done; if you take a gun and shoot black sand, through 2 slits on a metal plate with a white wall behind it you will get an image that looks like this on the white wall:
I I
If you point a flashlight through the 2 slits you will get an image on the wall that looks like this:
I I I I I I I I
This is called an interference pattern and you may notice how the lines in the middle are stronger than the ones on the edges as is common in all experiments done with light waves - water ripples are similar to light waves. Everything in our present existence is made of either matter (solid particles) or light.
This experiment is a basic yet very effective method of differentiating between waves and what is composed of particles -- or matter - on the atomic level.
Back to electrons: when scientists shot electrons through the plate with the double slit the result was that of a wave
I I I I I I I I
This drove the scientific community nuts as they thought that electrons were particles made of matter. After much controversy, theories as to why, and repeated experiments scientists decided to watch exactly what the electrons were doing as they passed through the 2 slits. The result that followed turned the world of physics around. When the electrons were observed the result was:
I I matter
When the observation device was switched off the result was again:
I I I I I I I I a wave
Electrons would switch from waves into matter particles instantly and only when scientists were observing them. Did the electrons seem to know somehow when they were being watched and would snap into being particles of matter and "behave" only when they were being observed? For anything on the planet to be switching back and forth from waves into matter is impossible. - It does not compute. This phenomenon is now called in Quantum "The Collapse of a Wave."
The Collapse of a Wave has been one of the most startling discoveries of Quantum Physics. Physicists have a stream of theories, but this simple yet unexplainable experiment declared to humanity that everything we are looking at-- as completely irrational as it may seem - on the quantum level - turns into reality or solid form - only when it is observed. No one really knows what is going on down there; there is no real explanation possible. Without the observer - nothing is solid.
Einstein grew increasingly troubled by the "Collapse of a Wave" and toward the end of his life at one point during a heart-to-heart talk with physicist Abraham Pais asked "Do you really believe the moon exists only when I look at it?" Does everything only exist when it is being observed? This would mean consciousness is creating what we see with our eyes. Many theories have been given in regards to the Collapse of a Wave; the most popular being co-dimensions existing at the same time and electrons are switching back and forth between them.
Another is the existence of a sort of "fabric" that connects everything in the universe. When consciousness "observes" the fabric then the solid image forms ...
Presently all quantum physics equations now have the "observer" factor added. Stephen Hawkings recently said that whoever can decipher Quantum has deciphered the language of the universe.
I give a derivation of Young's double slit formula. The double slit formula is used to find the pattern ...that the interference of two light waves create when they pass through double slits in a diffraction grating.
Young's double slit formula connects the distance between two slits in a diffraction grating, the distance from the diffraction grating to the wall, the distance between points of maximum constructive interference, and the wavelength of light.
0:00 What the Equation is Predicting 1:33 Path Difference, and Constructive and Destructive Interference 5:26 Drawings of Double Slit Experiments are Exaggerated 5:40 The Visual Pattern of Constructive and Destructive Interference 6:01 Proving the Equation
Now that we have proved Young's Double Slit Interference Equation, we can [...]
Now that we have proved Young's Double Slit Interference Equation, we can use it to solve for missing variables in the double slit experiment like the length between maxima, distance ...between the wall and the diffraction grating, the distance between the double slits, and the wavelength of the light.
Diffraction Gratings in a Snap! Unlock the full A-level Physics course at [...]
Diffraction Gratings in a Snap!
Unlock the full A-level Physics course at http://bit.ly/2KciSK5 created by Elisavet, Physics expert at SnapRevise.
SnapRevise is the UK’s leading A-level and GCSE revision & exam ...preparation resource offering comprehensive video courses created by A* tutors. Our courses are designed around the OCR, AQA, SNAB, Edexcel B, WJEC, CIE and IAL exam boards, concisely covering all the important concepts required by each specification. In addition to all the content videos, our courses include hundreds of exam question videos, where we show you how to tackle questions and walk you through step by step how to score full marks.
Sign up today and together, let’s make A-level Physics a walk in the park!
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Measuring Wavelength of Light with a Diffraction Grating - PRACTICAL - A Level Physics
In this video I go through an AQA Physics A Level Required Practical that [...]
In this video I go through an AQA Physics A Level Required Practical that uses a diffraction grating experiment to investigate the properties and to measure the wavelength of light. ...(This is AQA Required Practical 2.) This is also the OCR A Level Physics PAG 5.1 Practical.
A laser will diffract and interfere when shone through a diffraction grating. The distance to the first, second and third order maxima can be measured which will then allow the wavelength of the light to be calculated. Be careful with the laser. Do not look at the beam or any reflected light from a shiny surface.
MY YOUTUBE CHANNEL Your support in watching this video has been invaluable! To contribute towards the free videos on YouTube, make a small donation at: ► https://www.paypal.me/physicsonline
This is a topic which introduces the detail of the atom, the idea of stability, the photon model E = hf, antiparticles and the interactions of particles. There is quite a lot of wordy detail and basic facts to learn with a small number of calculations such as specific charge or E = hf to cover. Also make sure you know what an electron volt is and how to derive it from first principals. Energies may also be expressed in Joules or MeV so be sure on that one as well. Also you must visit https://www.particleadventure.org/ to read around the first three topics. If you don’t you will fail the exam! But a word of caution you will not need to know everything on the site. The AS Physics Exam does not cover every particle in the universe so check the specs!
Video to introduce AS Physics for AQA. The first topic covers mainly [...]
Video to introduce AS Physics for AQA. The first topic covers mainly specific charge as a key concept.
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1.2 neutrinos.flv
Physics explaining the neutrino
Physics explaining the neutrino
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Radioactive Decay of Carbon 14
Short clip explains the radioactive decay of carbon-14 and how C-14 can be [...]
Short clip explains the radioactive decay of carbon-14 and how C-14 can be used for radiometric dating
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British Museum Gebelein Man - Oldest Mummy found in the World!
Gebelein, Egypt, Predynastic period, around 3500 BC A naturally preserved [...]
Gebelein, Egypt, Predynastic period, around 3500 BC
A naturally preserved mummy in a reconstructed pit-grave.
This man died more than five thousand years ago and was buried at the site of Gebelein, ...in Upper Egypt. The reconstruction of his grave illustrates the early Egyptian custom of placing the body in a contracted, foetal position, usually on the left side, with the head to the south, facing the west, the land of the dead where he would be reborn. Around him were all the things he might need for his afterlife, especially pottery to hold and serve food.
In the Predynastic period (4400-3100 BC), the time before the pharaohs, the dead were buried in shallow graves cut into the desert sand. The graves were often lined with reed mats, making them like a bed, and the body was covered with linen or skins and more mats, like a blanket, before the grave was refilled and perhaps topped by a mound of dirt. Contact with the hot dry sand naturally preserved the bodies because the sand absorbed the water that constitutes approximately 75% by weight of the human body. Bacteria cannot breed without moisture and as a result, the bodies frequently did not decay, but simply dried out. The body of this man is remarkably well-preserved, even down to his finger-nails and hair, which has probably faded with time.
Chance discoveries of these sand-dried mummies (for example, when a grave was disturbed by animals or robbers), may have promoted the belief that physical preservation of the body was necessary for the afterlife. This may have led the later Egyptians to develop means of artificial mummification after the introduction of coffins and deeper graves separated the body from the natural drying effects of the sand.
The objects that surrounded Gebelein Man in his original burial are unknown. On display is a selection of typical grave-goods from other graves of the middle Predynastic period (about 3500 BC), the time we believe he died. Attempts to date the body using Carbon 14 (the radiocarbon method) have so far been unsuccessful
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GCSE Science Revision - Carbon Dating
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What led physicists to propose the existence of neutrinos?
Neutrinos have long been a part of the Standard Model of particle physics, [...]
Neutrinos have long been a part of the Standard Model of particle physics, but their introduction to that model was a result of physicists missing something in their reactions. Brian ...Greene explains.
Subscribe to our YouTube Channel for all the latest from World Science U.
Scientists are aware of four fundamental forces- gravity, electromagnetism, [...]
Scientists are aware of four fundamental forces- gravity, electromagnetism, and the strong and weak nuclear forces. Most people have at least some familiarity with gravity and electromagnetism, but not the ...other two. How is it that scientists are so certain that two additional forces exist? In this video, Fermilab’s Dr. Don Lincoln explains why scientists are so certain that the strong force exists.
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The Four Fundamental Forces - IB Physics
Lecture on Gravity: https://www.youtube.com/watch?v=CkmJQdUS0W0 Lectures on [...]
Lecture on exchange particles/bosons: (coming soon)
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The Photon - A Level Physics
This video introduces and explains the Photon for A Level Physics. What [...]
This video introduces and explains the Photon for A Level Physics.
What exactly is a photon? This video shows how we can use the particle model, with individual corpuscles of energy, ...to explain certain properties of EM radiation. In quantum physics we discover a phenomena called wave-particle duality - this is very important for understanding the photon.
MY YOUTUBE CHANNEL Your support in watching this video has been invaluable! To contribute towards the free videos on YouTube, make a small donation at: ► https://www.paypal.me/physicsonline
Everyone has seen them, lasers, and have probably teased many cats with [...]
Everyone has seen them, lasers, and have probably teased many cats with them. Just how do those little devices manage to put out this nice beam of light? Lasers are ...ubiquitous not only in scientific research but also industry – knowing why this is and how they work is the motivation behind discussing it.
This video is a complete guide to how a laser works.
The group of particles that include the fundamental leptons and quarks as [...]
The group of particles that include the fundamental leptons and quarks as well as the quark composites called hadrons are all fermions. They are the building blocks of matter. The ...video lesson describes the main properties of each and provides useful summaries. Notes to support this video are available here: https://www.fizzics.org/fermions-quarks-leptons-and-hadrons-the-building-blocks-of-our-universe/
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AQA AS Physics Feynman diagrams
This video is a quick introduction to the rules of feynman diagrams for AS [...]
This video is a quick introduction to the rules of feynman diagrams for AS Physics. Some very useful rules here!
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Feynman Diagrams - A Level Physics
This video introduces and explains Feynman Diagrams for A Level Physics. [...]
This video introduces and explains Feynman Diagrams for A Level Physics.
Feynman diagrams should be familiar to you as the Physics Online logo is one! Particle interactions are described by Feynman ...diagrams as they interact. Two particles, that interact via a force, exchange a force exchange particle called a boson which 'carries' the force.
An important interaction that we can display with a Feynman diagram is beta decay.
Thanks for watching,
Lewis
This video is recommended for anyone studying A Level Physics in the following exam boards: AQA CIE Eduqas WJEC
_____________________________________
MY PHYSICS WEBSITES Find even more videos organised by exam board and topic at:
MY YOUTUBE CHANNEL Your support in watching this video has been invaluable! To contribute towards the free videos on YouTube, make a small donation at: ► https://www.paypal.me/physicsonline
This is a test designed to check if you understand Chapter 1 of the work you have completed. Only attempt this quiz when you have revised or you will not get a top score. When you get a score you are happy with let you teacher know so they can put it in their markbook.
Start
Congratulations - you have completed AS Chapter 1 Matter and Radiation. You scored %%SCORE%% out of %%TOTAL%%. Your performance has been rated as %%RATING%%
Your answers are highlighted below.
Question 1
Electrons are negatively charged -1.6 x 10-19C and have an opposite charge to that of a proton. What is the charge on the proton?
A
-1
B
+1.0 x 10^(-19)C
C
+1
D
-1.6 x 10^(-19)C
E
+1.6 x 10^(-19)C
Question 2
Neutrinos: These are produced in the Sun by the weak interaction (β+ or β- decay). They have no charge or mass and are not affected by strong or electromagnetic force. They are fundamental particles. There are three types, or “flavours”, of neutrinos: electron neutrinos, muon neutrinos and tau neutrinos. Each type also has a corresponding antiparticle, called an antineutrino with an opposite chirality. When we have a beta + decay and beta - decay we produce.....
A
b+.........electron + electron antineutron
b-..........positron + electron neutrino
B
b-.........electron + electron antineutron
b+..........anti positron + electron neutrino
C
b-.........anti electron + electron antineutron
b+..........positron + electron neutrino
D
b-.........electron + electron antineutron
b+..........positron + electron neutrino
Question 3
Rutherford did an experiment to investigate the nucleus. He fired alpha particles at the nucleus and found that most went through and a few returned deflected at 180° or near to. The conclusion was that.....
A
the nucleus was negative with particles around it
B
the nucleus is large and very positive with a lot of empty space around it
C
the nucleus was very small and very positive with a no empty space around it
D
the nucleus was very small and very negative with a lot of empty space around it
E
the nucleus was very small and very positive with a lot of empty space around it
Question 3 Explanation:
It makes perfect sense and usually gets you two marks if you put a full answer!
Question 4
The electrostatic force.....
A
Affects all charged particles i.e. protons, electrons, positrons, muons etc.. either attract or repel each other. The force gets very large at small separations. W- / W+ is the exchange particle
B
Affects all charged particles i.e. protons, electrons, positrons, muons etc.. either attract or repel each other. The force gets very large at small separations. Photon is the exchange particle
C
Affects all anti particles either attract or repel each other. The force gets very large at small separations. Photon is the exchange particle
D
Affects all neutral particles i.e. neutrons, neutrinos etc.. either attract or repel each other. The force gets very large at small separations. Photon is the exchange particle
Question 5
Here are all the isotopes of carbon. Can you correctly work out what particle is emitted in each case? C14 (5730 years T1/2) C13 C12 C11 (20.3min T1/2) C10 (19.2s T1/2)
A
Beta-,0,0,Beta+,Beta+
B
Alpha,0,0,Alpha,Alpha
C
Beta+,0,0,Beta-,Beta-
D
All Beta -
E
Alpha, Beta+, Beta+, Beta -, Beta -
Question 6
Protons and Neutrons make up the nucleus. They have a mass of 1 relative to each other but an actual mass of 1.67 x 10-27kg. The proton carries a charge of +1.6 x 10-19C. In certain calculations you must use the actual values. What is the charge to mass ratio of proton or neutron....
A
1/4
B
1
C
1.04 x 10^(-6)C/kg
D
95808383C/kg
E
-1
Question 6 Explanation:
Simply work out the total charge / total mass!
Question 7
Cloud Chambers: These chambers show us charged particles by creating droplets in a saturated gas. The particles can be deflected by a magnetic field and show momentum and charge +/- to an observer. Carl Anderson found the positron by this method. What do they show?
A
That anti-particles were not detected.
B
That charged particles curve one way, and an antiparticle will curve the opposite way but by the same amount.
C
That charge particles curve one way, and an antiparticle will curve the opposite way but by twice the amount of the particle.
D
That charged particles curve one way, and an antiparticle will curve the same way but by the same amount.
Question 8
Pair Production only occurs when.... the photon energy E= hf = hc/λ is greater than or equal to 2mc2, where m is the mass of the particle, with rest energy mc2 for each particle of the pair produced.
A
The photon energy E= hf = hc/λ is greater than or equal to 2mc^2, where m is the mass of the particle, with rest energy mc^2 for each particle of the pair produced.
B
The photon energy E= hf = hλ/c > 2mc^2, where m is the mass of the particle, with rest energy mc^2 for each particle of the pair produced.
C
The photon energy E= hf = hc/λ is less than 2mc^2, where m is the mass of the particle, with rest energy mc^2 for each particle of the pair produced.
D
Very far from the nucleus of an atom when E= hf is less thatn 2mc^2
Question 9
Instead of thinking of the removal of an electron as -1 or the atoms charge becomes +1 to form a +1 ion i.e. Na+. Mass or p or n = 1.67 x 10-27kg. The proton carries a charge of +1.6 x 10-19C. Now we think about ions as having an overal charge of…. 1.6 x 10-19C -> +1 3.2 x 10-19C -> +2 4.8 x 10-19C -> +3 If we think about a Magnesium atom (24 mass, 12p) becoming a +2 ion what would the specfic charge of the ion be?
A
1.24 x 10^(-7) C/kg
B
8.04 x 10^(6) kg/C
C
3.2 x 10^(-19) C
D
8.04 x 10^(6) C/kg
E
1.24 x 10^(-7) kg/C
Question 9 Explanation:
You need to work out that Magnesium has lost 2 electrons or 3.2x10^(-19)C
Question 10
Isotopes are simply elements with more or less neutrons. This means that they can be more unstable than the ones usually found in the periodic table. Often Isotopes appear in small % so effect the relative mass of a sample. Carbon is a good example with many isotopes. An example of an Isotope of Carbon would be...
A
13n, 12p, 12e
B
14n, 14p, 14e
C
12n, 13p, 12e
D
13n, 13p, 13e
Question 11
What best describes the strong force or interaction Acts on nucleons only as they contain quarks. It keeps the nucleus stable; short-range attraction to about 3 fm, very-short range repulsion below about 0.5 fm. This balance causes nucleons to be happy at the distance to make a stable atom.
A
Acts on nucleons only as they contain quarks. It keeps the nucleus stable; short-range attraction to about 3 fm, very-short range repulsion below about 0.5 fm.
B
Acts on protons only as they contain quarks. It keeps the nucleus stable; long-range attraction to about 3 fm, very-short range repulsion below about 0.5 fm.
C
Acts on nucleons only as they contain quarks. It keeps the nucleus stable; long-range attraction to about 3 fm, very-long range repulsion below about 0.5 fm.
D
Acts on charged particles only as they contain quarks. It keeps the nucleus stable; short-range attraction to about 3 fm, very-short range repulsion below about 0.5 fm.
Question 12
Rest Energy: Sometimes we talk of the rest energy of a particle. This is the energy it takes to form a particle. The units we usually use to express this are Joules or electron volts. However, we often use MeV or GeV which
A
are 1 x 10^(6)eV or 1 x 10^(9)eV respectively.
B
are 1 x 10^(9)eV are or 1 x 10^(6)eV respectively.
C
are 1 x 10^(6)eV are or 1 x 10^(3)eV respectively.
D
are 1 x 10^(3)eV are or 1 x 10^(6)eV respectively.
Question 13
What is special about W+ & W- Bosons:
A
The W Boson is an exchange particle which has a very short life time 10^(-27) s so it does not travel very far.
B
The W Boson is an exchange particle which has a very short life time 10^(-19) s so it does not travel very far.
C
The W Boson is an exchange particle which has a very long life time 10^(27) s so it does not travel very far.
D
The W+ Boson is an exchange particle which has a very short life time 10^(-27) s and then turns into a W- after this time.
Question 14
“Positron Emission Tomography” is a process where a radioactive tracer is injected into the body. The body then metabolises the isotope at a certain rate. The isotope then decays and producing a position which decays into two gamma ray photons when it hits an adjacent electron. These photons are picked up and mapped to produce 3D images. What fundamental force is used to detect the boson used to visualise the effect....
A
weak
B
electromagnetic
C
graviton
D
strong
Question 15
What is the energy of a 600nm EM wave c = 3.00 x 108 ms-1 h = 6.63 x 10-34Js
A
1.07eV
B
2.3 x 10^(-19)J
C
7.02eV
D
3.32 x 10^(-19)J
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This topic is about learning what is inside a nucleus and essentially how does that make an atom behave. You really need to learn a lot of basic facts. You can also find loads of youtube movies, just search for the key terms and you will learn lots of things.
Pb210 Source showing background alpha and neutrino, muons and other cosmic rays in a cloud chamber.
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Cloud Chamber Cosmic Rays
Pb210 Source showing background alpha and neutrino, muons and other cosmic [...]
Pb210 Source showing background alpha and neutrino, muons and other cosmic rays in a cloud chamber.
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Cloud Chamber and Alpha source.
This video shows Pb210 in a Pasco cloud chamber. You can clearly see the [...]
This video shows Pb210 in a Pasco cloud chamber. You can clearly see the tracks form as the alpha particles hit the alcohol vapour "cloud" in the chamber. They are ...all very similar and linear as the particles have roughly the same energy in the splitting atom.
Particle Physics: Mesons in a Snap! Unlock the full A-level Physics course [...]
Particle Physics: Mesons in a Snap!
Unlock the full A-level Physics course at http://bit.ly/382q7Pg created by Elisavet, Physics expert at SnapRevise.
SnapRevise is the UK’s leading A-level and GCSE revision & ...exam preparation resource offering comprehensive video courses created by A* tutors. Our courses are designed around the OCR, AQA, SNAB, Edexcel B, WJEC, CIE and IAL exam boards, concisely covering all the important concepts required by each specification. In addition to all the content videos, our courses include hundreds of exam question videos, where we show you how to tackle questions and walk you through step by step how to score full marks.
Sign up today and together, let’s make A-level Physics a walk in the park!
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Baryons and Mesons in terms of their Quarks - A Level Physics
What did the fundamental duck say? Quark Quark! Exploring what happens when [...]
What did the fundamental duck say? Quark Quark! Exploring what happens when you mix together different quarks to make the two types of Hadrons - the heavier Baryons made from ...3 quarks and the lighter Mesons from from a quark and an antiquark. This is where it starts to get strange.
Thanks for watching,
Lewis
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Excitement Grows As Large Hadron Collider Hints At New Particle https://www.theguardian.com/science/2016/mar/18/excitement-grows-over-large-hadron-colliders-possible-new-particle-lhc "When hundreds of physicists gathered this week in La Thuile, an old mining town in the heart of the Italian alps, one short and simple question hung in the cool, crisp air: is it real? The source of their fascination, and no little excitement, was light. Not the sunlight that made the snow glint on the mountains in the Aosta valley, but light inside the Large Hadron Collider (LHC) across the border near Geneva. The machine had detected more photons than expected as it smashed particles beneath the quiet Swiss countryside. The brief flashes of light might be the first glimpse of the next big discovery."
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Quarks and leptons for beginners: from fizzics.org
Quarks and leptons are fundamental particles making up all the normal [...]
Quarks and leptons are fundamental particles making up all the normal matter we know. The properties and differences are briefly explained with an introduction to the way quarks exist together ...to make up other particles such as hadrons. Notes and many more video lessons available here https://www.fizzics.org/fizzics-guide/ A prequel video Bosons and Fermions for beginners is here https://youtu.be/xNrTry27lC4
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Strange Particles
An introduction to strangeness and strange particles.
An introduction to strangeness and strange particles.
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Particle Physics - Conservation Laws - A Level Physics Revision
A short video explaining how we can verify the fundamental interactions [...]
A short video explaining how we can verify the fundamental interactions that occur between fundamental particles. Energy, momentum, charge, baryon number, lepton number, strangeness. How to apply them ...to Nuclear Equations. A Level Physics Revision. Particle Physics. Including matter and antimatter.
At Gorilla Physics we’re all about you understanding more, so you get more confident, then enjoy Physics more and then you’ll do better in your GCSE and A Level Physics exams.
This is a test designed to check if you understand Chapter 2 of the work you have completed. Only attempt this quiz when you have revised or you will not get a top score. When you get a score you are happy with let you teacher know so they can put it in their markbook.
Start
Congratulations - you have completed AS Chapter 2 Quarks and Leptons. You scored %%SCORE%% out of %%TOTAL%%. Your performance has been rated as %%RATING%%
Your answers are highlighted below.
Question 1
For any interaction to occur we must have conservation of...
A
baryon, lepton, charge, strangeness
B
lepton number
C
strangeness
D
charge
E
baryon number
Question 2
Neutrinos are...
A
chargeless and are created in B+/- decay in the sun.
B
massless, chargeless and are created in B+/- decay in the sun.
C
massless and are created in B+/- decay in the sun.
D
massless, chargeless and the antiparticle of the positron
Question 3
Which choice best describes a muon....
A
The muon is unstable with a long mean lifetime of 2.2 µs, it is a lepton and has a charge of -1.6 x 10^(-19)C. It always decays into three particles.
B
The muon is unstable with a long mean lifetime of 22 µs, it is a lepton and has a charge of +1.6 x 10^(-19)C. It always decays into three particles.
C
The muon is stable and has a charge of -1.6 x 10^(-19)C
D
The muon is unstable with a long mean lifetime of 2.2 µs, it is a lepton and has a charge of -1.6 x 10^(-19)C. It always decays into two particles.
Question 4
Which answer is true for all hadrons
A
Hadrons are unstable with the exception being the proton-the only stable Hadron.
B
Hadrons are stable with the exception being the proton-the only unstable Hadron.
C
All hadrons contain 2 quarks
D
All hadrons contain 3 quarks
Question 5
Which of these particles contains a strange quark
A
kaon only
B
kaon, pion, muon
C
pion only
D
kaon, pion
E
muon only
Question 6
A mesons internal structure best described as consisting of....
A
antiquark - antiquark pair
B
quark - quark pair
C
three or two quarks
D
always two quarks
E
quark and antiquark pair
Question 7
When a π- and proton collide in the LHC at high speed they produce a K+ and Σ- particles w hich then decay further. The strangeness of the Ko is +1 What is the strageness of the Σ- particle produced?
A
+1
B
-2
C
-1
D
+2
E
0
Question 8
The Quarks inside a proton and antiproton are...
A
ud
B
uud and anti-u, anti-u, anti -d
C
udd and anti-u, anti-d, anti -d
D
uu anti-d and anti-u, anti-u, d
E
uds
Question 9
Which statement about a kaon is all true....
A
Kaons decay “strangely” or last longer than they should for their mass. They contain a strange or anti-strange quark.
B
Kaons decay “strangely” or last a shorter time than they should for their mass.
C
They contain a double strange or anti-strange quark.
Question 10
Powell discovered which particles at high altitudes when he exposed photgraphic plates to the atomosphere proving Yukawa's theories....
A
Pi-mesons
B
Muons
C
K-mesons
D
Protons
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This chapter covers the quantum phenomena of the photoelectric effect, excitation, fluorescence and line spectra. What is most important is to learn the ideas of photoelectric effect so you can construct a wordy answer to a 6-7 mark written question. Also make sure you know your Joules from your eV’s. Finally there are a lot of computer models to look at which help you visualise this topic make sure you spend the time looking through them
In this video a range of seven LEDs are used to investigate the relationship between photon energy and frequency so that a value for Planck's constant can be estimated.
* Heads up: the value of Planck's constant obtained in this experiment is an estimate and as you will find my value is very different to the data book value. It's quite bad on one level, but on another it may be useful for evaluation! *
Experiments about quantum concepts, like this one, are mandatory practicals for many physics specifications. So this is good practice for OCR physics A, AQA A-Level physics, Edexcel A-Level physics, CPAC, PAG, practical endorsement.
In this video a range of seven LEDs are used to investigate the [...]
In this video a range of seven LEDs are used to investigate the relationship between photon energy and frequency so that a value for Planck's constant can be estimated.
* Heads up: the value of Planck's constant obtained in this experiment is an estimate and as you will find my value is very different to the data book value. It's quite bad on one level, but on another it may be useful for evaluation! *
Experiments about quantum concepts, like this one, are mandatory practicals for many physics specifications. So this is good practice for OCR physics A, AQA A-Level physics, Edexcel A-Level physics, CPAC, PAG, practical endorsement.
A Scottish chemist called Joseph Swann tried passing electricity through fine wires (filaments) to make them glow white hot in 1860. Despite enclosing them in bulbs and pumping out the ...air, they quickly broke or blackened and Swann abandoned the idea. 17 years later, finding a better vacuum pump, he tried again. With no air left inside, the filament light bulb became a practical proposition.
Thanks to Tim Hunkin the creator for allowing these excellent videos to be freely distributed on-line.
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http://www.nucleushealth.com/ - This medical animation depicts Laser Eye Surgery, a procedure that permanently changes the shape of the cornea, the clear covering over the front of the eye. #lasik #eye #cornea ANCE00185
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Fluorescent Lamps Explained with Quantum Physics - A Level Physics
This video introduces fluorescent lamps and explains them with quantum [...]
This video introduces fluorescent lamps and explains them with quantum physics for A Level Physics.
These common light fittings are used because they are relatively cheap and highly efficient. A glass ...tube is filled with mercury vapour at a low pressure. When excited by electrons the mercury atoms become ionised, losing an electron. As the electron returns to its ground state, it then emits an ultraviolet photon. A phosphor coating on the inside of the tube then absorbs the UV photon, finally emitting a range of visible photons which we see as white light.
Thanks for watching,
Lewis
This video is recommended for anyone studying A Level Physics in the following exam boards: AQA CIE Edexcel Edexcel IAL Eduqas IB OCR A OCR B WJEC
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How to demonstrate electron diffraction in the classroom
This demonstration shows that an electron beam is diffracted when it passes [...]
This demonstration shows that an electron beam is diffracted when it passes through graphite, showing electron wave behaviour and diffraction patterns.
The wave particle duality concept is central to understanding quantum [...]
The wave particle duality concept is central to understanding quantum physics. The A level specification introduces the DeBroglie equation and this experiment uses it along with the diffraction equation to ...find the spacing between carbon atoms in graphite.
A teacher must be present at all times during this experiment due to high voltages to the electron gun in the vacuum tube.
Phil Furneaux Ogden Science Officer Lancaster University 26th Jan 2017
Plasma Ball Excitation of a fluorescent lamp & CFL
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A plasma globe or plasma lamp (also called plasma ball, dome, sphere, tube or orb is a clear glass sphere filled with a mixture of various noble gases with a ...high-voltage electrode in the center of the sphere. Plasma filaments extend from the inner electrode to the outer glass insulator, giving the appearance of multiple constant beams of colored light
The plasma lamp was invented by Nikola Tesla after his experimentation with high-frequency currents in an evacuated glass tube for the purpose of studying high voltage phenomena
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We can use this one to allow electrons to flow into a low pressure mercury gas. The atoms become excited by collisions with electrons and an atomic electron is moved up an electron shell. We call this an “excited atom”. Sometime later the gas stops being excited as the electron falls back to its original shell emitting a photon of UV light. Then this photon of light is absorbed by the coating on the glass which has a similar process but this gives out a visible photon which you can see. This is a quantum effect and the bulb will only give out certain colours of light.
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When the energy gap between two molecular energy levels is exactly the same [...]
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Spectral lines shown on a spectroscope from a neon geissler tube. This is a [...]
Spectral lines shown on a spectroscope from a neon geissler tube. This is a great quantum effect!
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This is a simple experiment to show how colours of light can be split into [...]
This is a simple experiment to show how colours of light can be split into individual wavelengths of light using a simple diffraction tube.
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Its amazing how you can make the light move up the tube with a plasma ball!
Its amazing how you can make the light move up the tube with a plasma ball!
Title
What to do
Site
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Different excited states for different elements
Investigate exciting electrons by collisions – many atoms
This is the basic introduction to current flow and circuits. Really this unit is just an extension of GCSE Electricity with some harder problems using the same rules. Also you will need to remember how each component works and be able to interpret a VI graph. Always remember to check your gradient. Since V=IR a graph of V – y-axis and I – x-axis shows R as gradient. The other way around which is how we tend to do exp shows 1/R it does matter.
Electricity Calculations & Sig Figures….. I would advise all of you to look at this tutorial this week before you do the unit homework… https://www.chem.sc.edu/faculty/morgan/resources/sigfigs/index.html . An example is V = 12V, Resistance = 62Ω. If you work out the current through the resistor as V = IR changes to V/R = I = 12V/62 Ω = 0.193548A. The original data is 2 sig figures so you should quote the answer to this as well. Hence…
0.2A – Wrong 0.19A – Correct 0.193548A – Wrong
4.3 Resistance
resistivity (animation) Use this to think about how atoms actually look inside a metal. Then imagine a drift of electrons through this.
This section is about applying some more advanced rules to circuits that build on your GCSE skills. The trick is to realise that you must be 100% logical and treat it as a mathematical exercise. If you set up the problems correctly then you cannot go wrong. Take note of these things that you must be able to do…
Make sure you treat current and pd as having a direction.
Learn how to apply reciprocal equations for 1/R for resistors in parallel
Learn what the gradient and intercept mean on an Internal Resistance circuit graph
Remember that a power source is a “real source” and will get warm so lose energy! A 3V cell does not output 3V!
When thinking about potential dividers the trick is to realise that current is the same through each resistor. So setup two equations for V for each then I is the same for both!
This section is partly about learning to use and oscilloscope and partly about working out RMS currents and converting between A.C. and D.C. You must learn how to do both.
