Energy and Power in Circuits

Question 1

Energy is [ ] from cells and other sources

Answer 1

transferred

Question 2

Electricity is a form of energy therefore it’s always [ ]

Answer 2

conserved

Question 3

What component uses kinetic energy?

Answer 3

Motors

Question 4

What component uses light energy?

Answer 4

Bulb

Question 5

What component uses heat energy?

Answer 5

Hair dryers / kettles

Question 6

What component uses sound energy?

Answer 6

speakers

Question 7

What happens when current flows through anything with electrical resistance?
The more current that the [ ] that is produced

Answer 7

Electrical energy is converted into heat energy

more heat

Question 8

How does voltage effect the amount of heat due to resistance?

Answer 8

Bigger voltage means more heating because it pushes more current through

Question 9

How do filament bulbs work?

Answer 9

By passing a current through a very thin wire, heating it up so much that it glows. They waste a lot of energy as heat

Question 10

If an appliance is efficient it wastes [ ]

Answer 10

less energy

Question 11

What doe ‘more efficient’ appliances do?

Answer 11

Transfer more of their total electrical energy to useful energy

Question 12

Name 2 power-saving lamps that waste less heat energy than filament bulbs

Answer 12

1) Compact fluorescent lamps (CFLs)

2) Light-emitting diodes (LEDs)

Question 13

Energy Transferred =

power

Answer 13

Energy Transferred (kJ) = Power (kW) * Time (s)

Question 14

What is the formula for electrical power?

Answer 14

Power (W) = Current (A) * Potential Difference (V)

Question 15

What 3 ratings can you get on fuses in the UK?

Answer 15

3 A, 5 A or 13 A