Capacitance

Question 1

Define capacitance.

Answer 1

How much charge can be stored per unit potential difference.

C = Q/V

Question 2

Define the capacitance of a capacitor.

Answer 2

-Charge/potential difference
-It is the charge on one plate over the potential difference across the plates.

Question 3

Why when a capacitor is connected it stores energy and not charge.

Answer 3

-Net charge in the capacitor is zero as there are equal and opposite charges on the plates.
-It stores energy because the positive and negative charges are separated.

Question 4

What is the equation of the energy stored in a capacitor? both version

Answer 4

E = 1/2 C V^2
E = 1/2 Q V

Question 5

Define the Farad.

Answer 5

Unit of capacitance. Equal to the capacitance of a capacitor where one coulomb of charge causes a potential difference of 1 volt.

Question 6

Explain how energy is transferred and stored in a capacitor during the charging process.

Answer 6

-During charging of a capacitor, the power supply is used to push the electrons from one plate to another.
-Power supply does work on the electrons,
…increasing their potential energy.
-Which is recovered during discharging.

Question 7

If we have two capacitors connected in parallel one is charged the other is not what will happen?

Answer 7

-Some of the charge from the charged capacitor will go into the other capacitor.
-Transfer of charge will stop when the p.d.s are equal.