The Daniell cell is a type of electrochemical cell invented in 1836 by John Frederic Daniell, a British chemist and meteorologist, and consisted of a copper pot filled with a ...copper sulfate solution, in which was immersed an unglazed earthenware container filled with sulfuric acid and a zinc electrode. He was searching for a way to eliminate the hydrogen bubble problem found in the voltaic pile, and his solution was to use a second electrolyte to consume the hydrogen produced by the first. Zinc sulfate may be substituted for the sulfuric acid. The Daniell cell was a great improvement over the existing technology used in the early days of battery development. A later variant of the Daniell cell called the gravity cell or crowfoot cell was invented in the 1860s by a Frenchman named Callaud and became a popular choice for electrical telegraphy. The Daniell cell is also the historical basis for the contemporary definition of the volt, which is the unit of electromotive force in the International System of Units. The definitions of electrical units that were proposed at the 1881 International Conference of Electricians were designed so that the electromotive force of the Daniell cell would be about 1.0 volts. With contemporary definitions, the standard potential of the Daniell cell at 25 °C is actually 1.10 V[+] Show More
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Daniell cell - Volt Defined
The Daniell cell is a type of electrochemical cell invented in 1836 by John ...
The Daniell cell is a type of electrochemical cell invented in 1836 by John Frederic Daniell, a British chemist and meteorologist, and consisted of a copper pot filled with a ...copper sulfate solution, in which was immersed an unglazed earthenware container filled with sulfuric acid and a zinc electrode. He was searching for a way to eliminate the hydrogen bubble problem found in the voltaic pile, and his solution was to use a second electrolyte to consume the hydrogen produced by the first. Zinc sulfate may be substituted for the sulfuric acid. The Daniell cell was a great improvement over the existing technology used in the early days of battery development. A later variant of the Daniell cell called the gravity cell or crowfoot cell was invented in the 1860s by a Frenchman named Callaud and became a popular choice for electrical telegraphy. The Daniell cell is also the historical basis for the contemporary definition of the volt, which is the unit of electromotive force in the International System of Units. The definitions of electrical units that were proposed at the 1881 International Conference of Electricians were designed so that the electromotive force of the Daniell cell would be about 1.0 volts. With contemporary definitions, the standard potential of the Daniell cell at 25 °C is actually 1.10 V[+] Show More
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Sci Eye Electricity S096LS44 S120LS44
Scientific Eye Series 10 (1997) Eight programmes from the broadcast ...
Scientific Eye Series 10 (1997)
Eight programmes from the broadcast schools' science series, each of which examines a single topic, with individual stories being used to illustrate more general scientific ideas. ...
The individual titles are: Safety; The Solar System; Air Forces; Electricity; Rust; Fire; Rocks; Limestone.[+] Show More
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Series and Parallel Circuits and Resistance
Series To calculate the total overall resistance of a number of resistors ...
Series To calculate the total overall resistance of a number of resistors connected in series you add up the individual resistances. This is done using the following formula: Rtotal = R1 ...+ R2 +R3 and so on. This means that more bulbs means more resistance and lower current as V = IR. In this case it would be V = I*3R
Parallel When you add bulbs in parallel the resistances add up differently. 1/Rtotal = 1/R1 + 1/R2 + 1/R3. This means that instead of the example above there the resistance tripled.
1/RT = 1/R + 1/R + 1/R .....
1/RT = 3/R
R total = R/3
So.... V = IR becomes V = IR/3 so the resistance of the circuit overall drops off
3V/R = I so the current will triple and the bulbs will appear much brighter.
This is the advantage of a parallel circuit in that you can keep adding bulbs without reducing the current flow. However, of course this will consume more power in the circuit. This is how most home lighting is configured.[+] Show More
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Series and Parallel Circuits
Mr. Andersen contrasts series and parallel electrical circuits. A ...
Mr. Andersen contrasts series and parallel electrical circuits. A simulation is used to visualize electron flow through both circuit types.
This video covers: - The symbols of all the main components you need to ...
This video covers: - The symbols of all the main components you need to know - What LEDs are - The graphs and uses of LDRs and thermistors
General info: - Suitable for all ...GCSE and IGCSE courses - Suitable for higher and foundation tiers - Suitable for triple and combined science
Exam board specific info: AQA - Everything is relevant to your course! IGCSE Edexcel - Everything is relevant to your course! Edexcel - Everything is relevant to your course! OCR 21st Century - Everything is relevant to your course! OCR Gateway - Everything is relevant to your course![+] Show More
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Diodes - GCSE Physics
This video introduces diodes. These small components work like a one way ...
This video introduces diodes. These small components work like a one way valve, so the current only flows one way. If the potential difference is too great and the diode ...is connected the wrong way round, then the diode will break. Connected the right way round, a diode has a very small resistance for large values of potential difference.
The most common diode is the light emitting diode, an LED. An LED only emits light if it is connected to a circuit in the direction.
A diode is represented by a triangle connected to a line within a circle. The I-V graph of a diode is very distinctive because it only allows current to flow through one way.
Thanks for watching,
Lewis
Relevant for GCSE Physics 9-1 in the following exam boards: AQA (including Trilogy) Edexcel OCR A OCR B WJEC CIE (Cambridge International Examinations) IGCSE (Physics Higher only) Edexcel International IGCSE
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This one was a little bit tricky! Loose connection bit still shows the idea.
This one was a little bit tricky! Loose connection bit still shows the idea.
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Q4 and 5 5B SLG and 2C Elec and PD June 2018 iGCSE Physics
This is a quick video walkthrough of an Edexcel exam question. It is ...
This is a quick video walkthrough of an Edexcel exam question. It is designed so you can look at questions which relate to questions from specific parts of the course.
It ...is taken from a real paper and I have used a real mark scheme which I have adapted for on-screen use. If you listen carefully it will give you a really good idea of what an examiner is looking for.[+] Show More
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Q8 2C Electrical Circuits June 2018 iGCSE Physics
This is a quick video walkthrough of an Edexcel exam question. It is ...
This is a quick video walkthrough of an Edexcel exam question. It is designed so you can look at questions which relate to questions from specific parts of the course.
It ...is taken from a real paper and I have used a real mark scheme which I have adapted for on-screen use. If you listen carefully it will give you a really good idea of what an examiner is looking for.[+] Show More
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AC v DC Diode Behaviour
Super cool demo of how diodes work in AC and DC currents. A diode will ...
Super cool demo of how diodes work in AC and DC currents.
A diode will flash at half the frequency of a filament lamp in AC situations.
You need a signal gen ...to see it or a high speed camera[+] Show More
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Resistance and Potential Difference models - GCSE Physics
Simple model to show PD, current and resistance with molymod.
Simple model to show PD, current and resistance with molymod.
Permanent link to this article: https://www.animatedscience.co.uk/igcse-physics-introduction-and-resources/2-electricity-part-a-units/2-electricity-part-c-electrical-energy-voltage