P2 - Electricity

Question 1

What is current?

Answer 1

Current is the flow of electrical charge, measure in amps.

Question 2

What is potential difference?

Answer 2

The driving force that pushes the charge around, measured in volts.

Question 3

What is resistance?

Answer 3

Resistance is anything that slows the flow down, measured in ohms.

Question 4

What is the equation for charge flow?

Answer 4

Charge flow (coulombs,C) = Current (A) x Time (s)

Question 5

What is the formula linking potential difference, current and resistance?

Answer 5

Potential difference (V) = Current (A) x Resistance (ohms)

Question 6

In a series circuit, what happens to the PD, current and resistance?

Answer 6

PD is shared (V_total = V₁ + V₂ +… )

Current stays the same ( I₁ = I₂ )

Resistance adds up.

Question 7

In a parallel circuit, what happens to the PD and current?

Answer 7

PD is the same ( V₁ = V₂ )

Current is shared ( I_total = I₁ + I₂ + … )

Question 8

What are the three main wires - what are thier colours, and what do they do?

Answer 8

Live wire (brown) - provides the alternating PD

Neutral wire (blue) - carries the current

Earth wire (green and yellow) - protection and safety

Question 9

In an electrical appliance, how do you work out the energy transferred?

Answer 9

Energy transferred (J) = Power (W) x Time (s)

Question 10

How do you find the power within an appliance?

Answer 10

Power (W) = potential difference (V) x Current (A)