Chapter 21 Capacitance

Question 1

What is a capacitor?

Answer 1

A capacitor is an electrical component where by charge is separated.

Question 2

After a capacitor is charged what is the relationship between the magnitudes of the charges on the positive and negative plate?

Answer 2

They are the same

Question 3

When the capacitor is connected to a cell what happens to the electrons from the positive plate?

Answer 3

They travel through the wires and through the cell and force themselves onto the negative plate, as more electrons try to get onto the negative plate the slower it charges as the electrons already on the plate are repelling the electrons in a wire.

Question 4

What is the definition of capacitance?

Answer 4

Capacitance is defined as the charge stored per unit p.d across it.

Question 5

How do you calculate the total capacitance for capacitors in series?

Answer 5

1/C(total) = 1/C1 + 1/C2 + 1/C3 …

Question 6

How do you calculate the total capacitance for capacitors in parallel?

Answer 6

C(total) = C1 + C2 + C3…

Question 7

How to calculate the energy stored in a capacitor from a graph?

Answer 7

Area under a voltage-charge graph W = 1/2 QV

Question 8

What is the constant ratio of decay?

Answer 8

For a given time interval the voltage will be in a constant ratio V1/V2 = V2/V3 + V3/V4

Question 8

What is the constant ratio of decay?

Answer 8

For a given time interval the voltage will be in a constant ratio V1/V2 = V2/V3 + V3/V4