electricity in the home

Question 1

types of electricity supplies

Answer 1

alternating current
direct current

Question 2

ac supplies

Answer 2

current is constantly changing direction, produced by an alternating potential difference in which the positive and negative ends keep alternating

Question 3

voltage of UK mains

Answer 3

230V

Question 4

frequency of ac mains

Answer 4

50Hz

Question 5

type of current in cells and batteries

Answer 5

direct current

Question 6

direct current

Answer 6

current that is always flowing in the same direction, created by a direct potential difference

Question 7

neutral

Answer 7

blue, completes the circuit, when appliance is operating current flows it, 0V

Question 8

live

Answer 8

brown, provides the alternating current from the mains, 230V, current flows through it

Question 9

earth

Answer 9

green and yellow, protecting the wiring and for safety, stops appliance casing from becoming live, doesn’t carry a current (only if a fault), 0V

Question 10

pd of each wire

Answer 10

neutral-0V
live-230V
earth-0V

Question 11

colour of each wire

Answer 11

neutral-blue
live-brown
earth-green/yellow

Question 12

why does touching the live wire give you an electric shock?

Answer 12

-body is at 0V
-a large pd is produced across your body and current flows through you
-causes a large electric shock

Question 13

why are plug sockets still dangerous even if switched off?

Answer 13

-still a pd in the wire which can cause an electric shock
-if you touched the live wire your body would provide a link between the supply and the earth so a current would flow through you

Question 14

what is dangerous in terms of the earth and the live wire?

Answer 14

any connection as it provides a link in which a current will flow