Electricity 8

Question 1

Current meaning

Answer 1

The amount of charges moving past a point in an electric circuit in one second

Question 2

Voltage meaning

Answer 2

1. The amount of electrical energy supplied to each charge so that it can move around an electric circuit.
2. The amount of electrical energy used up by a charge as it moves through a load/resistor.

Question 3

Series circuit meaning

Answer 3

An electric circuit where all components are connected one after the other so there is only one path for charges to flow around

Question 4

Parallel circuit meaning

Answer 4

An electric circuit in which components are connected alongside each other so that charges can flow through one or the other component, but not both, to complete the circuit.

Question 5

Energy efficiency meaning

Answer 5

The proportion of useful energy output from a device compared to the energy input, usually expressed as a percentage

Question 6

Generator meaning

Answer 6

A device that converts another form of energy into electrical energy

Question 7

How is current measured?

Answer 7

using an ammeter (amps)

Question 8

How is voltage measured?

Answer 8

using a voltmeter (volts)

Question 9

How do you calculate resistance?

Answer 9

R = Voltage ÷ Current

Question 10

State Ohm’s law

Answer 10

V (voltage) = I (current) x R (resistance)

Question 11

How does voltage change in different parts of a circuit?

Answer 11

Parallel: Same
Series: Splits

Question 12

How does current change in different parts of a circuit?

Answer 12

Parallel: Splits
Series: Same

Question 13

What happens to the current in a series circuit as more energy users are added?

Answer 13

It stays the same

Question 14

What happens to resistance in a series circuit as more energy users are added?

Answer 14

It increases

Question 15

What happens to voltage in a parallel circuit as more energy users are added?

Answer 15

The voltage for each user is the same as the voltage supplied

Question 16

What happens to the current in a parallel circuit as more energy users are added?

Answer 16

The current doubles

Question 17

What happens to resistance in a parallel circuit as more energy users are added?

Answer 17

It decreases

Question 18

Why are parallel circuits used in homes?

Answer 18

Because more lights can be added without them dimming

Question 19

What are energy transfers and transformations in a coal power station during the production of electricity?

Answer 19

Chemical energy from burning coal → thermal energy as it turns water into steam → kinetic from turbine turning → electric

Question 20

How do you calculate energy efficiency?

Answer 20

(useful energy ÷ total energy) x 100

Question 21

How do you interpret energy rating labels on electronics?

Answer 21

The more stars there are, the more energy efficient

Question 22

How is electricity generated using a magnet and coils in a coal power station?

Answer 22

The magnet is in the centre of the power turbine station with a large coil around it. The magnet moves creating a magnetic field which irritates the electrons, causing them to flow and create electricity.