Capacitors

W16 Activity 3 - Capacitors

By Nicholas Carrillo

​Conductors

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​Electric charge, e.g. electrons, are able to move around easily in conductors.

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​​Almost all metals are good conductors.

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Copper is a great conductor. ​

Charges have a difficult time moving around in insulators.

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Most materials are insulators.

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Wood is an insulator.​

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​Insulators

​Charges move in Electric Fields​

​Batteries provide the electric energy based on their voltage to push charges along.

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Connecting a batter to a lightbulb with wires forms a simple circuit.​

Multiple Choice

Charges move freely inside of...

• conductors

• insulators

Multiple Choice

Charges have difficulty moving in...

• Conductors

• Insulators

Multiple Choice

Electric charges in wires connected to a battery and light bulb are pushed by...

• The voltage from the battery

• The electric field from the battery

Two charged parallel metal plates held apart make a simple parallel-plate capacitor.

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Capacitors can store electrical energy.​

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Connecting a capacitor to a battery will cause charge to flow from the battery to the parallel plates.

​Capacitors

​Electric Charge is pushed onto the metal plates by the battery, but there's a maximum amount of charge that can be put on a capacitor.

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The amount of Charge per voltage is the capacitance.

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​C = Q/V

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Units in Farads (F) ​

A capacitor is charged with a 5V battery. The amount of charge is 1C.

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What is the capacitance for the capacitor?

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C = 1C/5V = 0.2 F​

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A 1 F capacitor is charged with a 5V battery. How much charge is stored in the capacitor?

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C = Q/V

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Q = C*V = 1F * 5V = 5C

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Q = 5C of charge​

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Multiple Select

Which of the following is true about capacitors?

• Capacitors store electrical energy.

• Capacitors have a maximum amount of charge they can store.

• Capacitors can store an infinite amount of charge.

• Capacitors are charged by connecting them to a voltage source. Like a battery.

Summary

The amount of charge stored on a capacitor per voltage is the capacitance.

C = Q/V

Capacitors store electrical Energy

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Charges move freely through conductors.

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Charges have a hard time moving through insulators.​

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​Electric charges are pushed by electric fields from voltage sources.