Charge, current and basic ideas

Question 1

What must a circuit have for charge to flow?

Answer 1

• A closed circuit
• A source of potential difference

Question 2

What is electric current?

Answer 2

• The flow of electrical charge

Question 3

What is potential difference?

Answer 3

• The energy transferred per unit charge

Question 4

What is resistance?

Answer 4

• A measure of how difficult it is for charge to flow

Question 5

What happens to current when resistance increases, for the same potential difference?

Answer 5

• Current decreases

Question 6

What happens to current when potential difference increases, for the same resistance?

Answer 6

• Current increases

Question 7

What is true about current in a single closed loop?

Answer 7

• It is the same at every point

Question 8

What are the units of current, potential difference and resistance?

Answer 8

• Current = amperes (A)
• Potential difference = volts (V)
• Resistance = ohms (Ω)