physics energy

What does a voltmeter measure

potential difference

What do thee ammeter measure

current

formula for ohms law

V=IR

what is alternating p.d

changes direction

what is direct p.d

p.d flows in one direction

what is a fuse

wire which melts when current gets to high, breaking the current

what does the earth wire do

carries charge to ground to prevent electroution

what colour is the earth wire

green and yellow

What colour is the live wire

brown

What colour is the neutral wire

blue

What is the p.d. of the live wire?

230V

What is the frequency of mains electricity

50Hz

what happenes to current in a series circuit

stays the same

What happenes to the p.d in the series circuit

shared

what do you do to the resistance in a series circuit

add

what happenes to the current in a parallel circuit

shared

what happenes to the p.d in a parallel circuit

same

What happenes when you add a resistor to a parallel circuit

changes resistance and current

what happenes to the resistance in a parallel circuit

lower than the lowest resistor

why does electric shock happen

high p.d between objects

formula for power

P=IV

P=I^2 x R

formula for energy

e=pt

e=vit

e=qv