# 23 Capacitors

This page covers the capacitors section of the course. One crucial part of this section is the ability to understand how to take Ln on an expoential function. You must make sure you work this out before you start the decay part. Also there are some tricky formulae again so you must make sure you make notes and go back to them to check what each thing is and when it applies. A capacitor has a current which changes all the time (unless charged with a constant current) so the formula are all time based.

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23 Capacitors Student Booklet

23 Capacitors Part B

23 Capacitors Part A

23.3 Challenge Sheet Flash

23.3 HSW Capacitor Planning Datalogging

23.3 Support worksheet capacitor graph

Picoscope Capacitor Decay

Capacitor Decay 47k 2200mF

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Natural Logarithms

This algebra video tutorial provides a basic introduction into natural [...]

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Logarithms... How? (NancyPi)

MIT grad introduces logs and shows how to evaluate them. To skip ahead: 1) [...]

MIT grad introduces logs and shows how to evaluate them. To skip ahead: 1) For how to understand and evaluate BASIC LOGS, skip to time 0:52. 2) For how to evaluate weirder logs, including the log of 0, 1, a FRACTION, or a NEGATIVE number, skip to time 6:44. 3) For NATURAL LOGS (LN X), skip to time 11:17. 4) For even weirder logs, including SOLVING for X and using the CHANGE-OF-BASE formula, skip to time 14:56. Nancy formerly of MathBFF explains the steps.

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1) BASIC LOGS: you can read log notation as "log, base 3, of 9 equals X". The small (subscript) number is called the base. You can always evaluate a log expression by rearranging it into something called exponential form. Every log expression is connected to an exponential expression. In this example, the log is connected to the exponential form "3 to the X power equals 9". This means, "3 raised to what power gives you 9?" Since 3 raised to the power of 2 equals 9, the answer for X is 2. This is also the answer for the value of the log expression. The log is always equal to the power (or exponent) in the exponential version, and in this case it equals 2. If you want, you can find the log value in your head just by asking yourself what power you need in order to turn the base number into the middle number ("argument" number). Note: if there is no base number in the log expression (no little subscript number), then the base is 10, since 10 is the default base.

2) WEIRDER LOGS (log of 0, 1, a negative number, or a fraction): you can use the same steps to rearrange log expressions that have a fraction, negative number, 0, or 1 in them. You can still rearrange them to be in exponential form just like you can with the basic logs from earlier. The log of 1 will always be 0, since 0 is the only power that can turn a base into 1. The log of 0 will always be undefined, since no power can turn a base into 0. The log of a negative number is undefined in the real number system, since no real power can turn a positive base into a negative number.

3) NATURAL LOGS (ln x): the natural log is just a special type of log where the base is e (the special math constant e, which is approximately 2.718 if you plug it into your calculator). You can use the same steps for rearranging the log expression into exponential form. Just remember that ln x means log, base e.

4) EVEN WEIRDER LOGS (solving for X, change-of-base formula): even if there is an X variable in the log part of an equation, you can still rearrange the equation into exponential form. This will let you solve for X. Sometimes you might need to use the change-of-base formula to evaluate a log expression. If there is no whole number power you know that works, it may actually be a decimal power that you can find by using the change-of-base formula. For example, you can re-write log, base 2, of 7 as (log 7)/(log 2) and use your calculator to find the decimal number if you need it.

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How Capacitors Work

Capacitors can store electrical energy and discharge it quickly, powering [...]

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Permittivity, Relative Permittivity And Dielectric Constant | Electrical4U

A SIMPLE explanation of permittivity (also known as relative permittivity [...]

A SIMPLE explanation of permittivity (also known as relative permittivity or Dielectric Constant. If you want to learn more about permittivity, you can learn more at: https://www.electrical4u.com/permittivity-and-relative-permittivity-or-dielectric-constant/

Relative permittivity is defined as the ratio of the actual or absolute permittivity of a medium to the absolute permittivity of a vacuum. The permittivity of a medium is expressed as ε. This ratio is 1.0006 for air. That means the relative permittivity of air is 1.0006.

The electrostatic force acting between nearby electrically charged bodies is inversely proportional to the permittivity of the medium.

Hence, the relative permittivity of any medium is defined as the ratio of force acting between nearby electrically charged bodies in the vacuum to the force acting between the same bodies separated by the same distance in the medium.

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Death Defying.....Super capacitor "Bin Bag" Static

Simple super capacitor with two sheets of aluminium and a plastic bag!

Simple super capacitor with two sheets of aluminium and a plastic bag!

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Capacitors in Series and Parallel Explained!

This physics video tutorial explains how to solve series and parallel [...]

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Capacitors in Series and Parallel

Intuitive explanation of why capacitors in series produce a smaller [...]

Intuitive explanation of why capacitors in series produce a smaller capacitance, and why capacitors in parallel produce a larger capacitance. My Patreon page is at

https://www.patreon.com/EugeneK active

Energy of a capacitor | Circuits | Physics | Khan Academy

This video explains the potential of a capacitor and how they function in a [...]

This video explains the potential of a capacitor and how they function in a circuit. By David Santo Pietro. Created by David SantoPietro.

Watch the next lesson: https://www.khanacademy.org/science/physics/circuits-topic/circuits-with-capacitors/v/capacitors-series?utm_source=YT&utm_medium=Desc&utm_campaign=physics

Missed the previous lesson? https://www.khanacademy.org/science/physics/circuits-topic/circuits-with-capacitors/v/capacitance?utm_source=YT&utm_medium=Desc&utm_campaign=physics

Physics on Khan Academy: Physics is the study of the basic principles that govern the physical world around us. We'll start by looking at motion itself. Then, we'll learn about forces, momentum, energy, and other concepts in lots of different physical situations. To get the most out of physics, you'll need a solid understanding of algebra and a basic understanding of trigonometry.

About Khan Academy: Khan Academy offers practice exercises, instructional videos, and a personalized learning dashboard that empower learners to study at their own pace in and outside of the classroom. We tackle math, science, computer programming, history, art history, economics, and more. Our math missions guide learners from kindergarten to calculus using state-of-the-art, adaptive technology that identifies strengths and learning gaps. We've also partnered with institutions like NASA, The Museum of Modern Art, The California Academy of Sciences, and MIT to offer specialized content.

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Capacitors - A Level Physics - Discharge and Exponential Decay - Revision

A video to show how to manipulate a exponential decay equation. This time [...]

A video to show how to manipulate a exponential decay equation. This time specifically a capacitor discharge circuit, but all the algebra here could apply to nuclear decay or any other exponential decay.

Also shown is how to fit the equation to a y = mx + c model (equation for a straight line) to use the gradient of a straight line as your graphical average.

You can now support GorillaPhysics by buying your next educational purchase from Amazon at my store:

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Capacitor charging and discharging

An explanation of the charging and discharging curves for capacitors, time [...]

An explanation of the charging and discharging curves for capacitors, time constants and how we can calculate capacitor charge, voltage and current.

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Dielectrics in capacitors | Circuits | Physics | Khan Academy

How dielectrics function in circuits. By David Santo Pietro. Created by [...]

How dielectrics function in circuits. By David Santo Pietro. Created by David SantoPietro.

Watch the next lesson: https://www.khanacademy.org/science/physics/magnetic-forces-and-magnetic-fields/magnets-magnetic/v/introduction-to-magnetism?utm_source=YT&utm_medium=Desc&utm_campaign=physics

Missed the previous lesson? https://www.khanacademy.org/science/physics/circuits-topic/circuits-with-capacitors/v/capacitors-parallel?utm_source=YT&utm_medium=Desc&utm_campaign=physics

Physics on Khan Academy: Physics is the study of the basic principles that govern the physical world around us. We'll start by looking at motion itself. Then, we'll learn about forces, momentum, energy, and other concepts in lots of different physical situations. To get the most out of physics, you'll need a solid understanding of algebra and a basic understanding of trigonometry.

About Khan Academy: Khan Academy offers practice exercises, instructional videos, and a personalized learning dashboard that empower learners to study at their own pace in and outside of the classroom. We tackle math, science, computer programming, history, art history, economics, and more. Our math missions guide learners from kindergarten to calculus using state-of-the-art, adaptive technology that identifies strengths and learning gaps. We've also partnered with institutions like NASA, The Museum of Modern Art, The California Academy of Sciences, and MIT to offer specialized content.

For free. For everyone. Forever. #YouCanLearnAnything

Subscribe to Khan Academy’s Physics channel: https://www.youtube.com/channel/UC0oGarQW2lE5PxhGoQAKV7Q?sub_confirmation=1

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Dielectrics & Capacitors - Capacitance, Voltage & Electric Field - Physics Problems

This physics video tutorial provides a basic introduction into dielectrics [...]

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Capacitors - A Level Physics

Continuing the A Level revision series looking at Capacitors. Includes [...]

Continuing the A Level revision series looking at Capacitors. Includes capacitance, how a capacitor works, the energy stored in a capacitor and the time for a capacitor to charge and discharge.Show More active

Capacitance - Physics A-level Practical

Mr Rees shows you how to find the capacitance of a capacitor using a [...]

Mr Rees shows you how to find the capacitance of a capacitor using a natural log (ln) graph.

**Permanent link to this article: **https://www.animatedscience.co.uk/23-capacitors

Theremin Prague Museum of Music

The theremin was the product of Soviet government-sponsored research into proximity sensors. The instrument was invented by a young Russian physicist named Lev Sergeyevich Termen (known in the West as Léon Theremin) in October 1920 after the outbreak of the Russian Civil War. After a lengthy tour of Europe, during which time he demonstrated his …