Using mains electricity safely and the power of electrical appliances

Question 1

Electrical appliances……….energy

Answer 1

Transfer.

Question 2

The power of an electrical appliance is the rate at which it….

Answer 2

Transforms energy.

Question 3

Define direct current

Answer 3

Current the always passes the batteries/cells in the same direction.

Question 4

Define alternating current

Answer 4

Current that is constantly changing direction.

Question 5

What type of current is mains electricity?

Answer 5

alternating current.

Question 6

oscilloscope traces

Answer 6

You can calculate the period and frequency of an alternating current.

Question 7

Core of electricity wires and why

Answer 7

Copper because it’s a good conductor.

Question 8

Outer layer of electricity wires and why

Answer 8

Plastic because it’s a good insulator.

Question 9

three wire types

Answer 9

Neutral, live and earth.

Question 10

Neutral wire colouring

Answer 10

blue

Question 11

live wire colouring

Answer 11

brown

Question 12

Earth wire colouring

Answer 12

Green and yellow stripes.

Question 13

What disconnects the current if there’s an electrical fault

Answer 13

A fuse or circuit breaker in the live wire.

Question 14

How do RCCBs operate?

Answer 14

The detect differences in the circuit between the live and neutral wires.

Question 15

What happens to the temperature in a resistor when a charge flows through it?

Answer 15

It increases.

Question 16

What bulb wastes a lot of energy through heat?

Answer 16

Filament bulbs.

Question 17

What is a better alternative to filament bulbs when it comes to saving energy?

Answer 17

Fluorescent lamps.

Question 18

Define power

Answer 18

The rate at which energy is transferred by an appliance.

Question 19

Calculate power(w)

Answer 19

energy(j)/time(s)

Question 20

calculate power(voltage and current)

Answer 20

Current(i)Xvoltage