P4

Question 1

How can we calculate energy transferred using potential difference and charge?

Answer 1

E =Q V

Question 2

Define resistance

Answer 2

The opposition to current flow

Question 3

What is Ohm’s law?

Answer 3

At a constant temperature, current through a component is proportional to potential difference

Question 4

Why is a filament lamp a non-Ohmic component?

Answer 4

The resistance increases as the current increases, due to its increase in temperature, so the current is not directly proportional to the potential difference

Question 5

What will happen to the resistance of a thermistor as the temperature increases?

Answer 5

The resistance will decrease

Question 6

What happens to the resistance of an LDR as light gets brighter?

Answer 6

It decreases

Question 7

How are components connected in series?

Answer 7

One after the other- if there is a break anywhere, charge will stop flowing

Question 8

What is the total resistance of a series circuit?

Answer 8

The total of the resistance of each component

Question 9

In a series circuit, will a component with higher resistance have a greater or smaller share of the potential difference?

Answer 9

Greater

Question 10

What does a variable resistor do?

Answer 10

Changes the resistance to keep the current constant