energy, power and resistance Flashcards
(10 cards)
1
Q
E.M.F
A
energy gained per unit charges passing through the supply
2
Q
potential difference
A
energy transferred per unit charge
3
Q
equation for EMF
A
energy transferred/charge
4
Q
equation for potential difference
A
work done/charge
5
Q
ohms law
A
current is directly proportional to the potential difference across it
6
Q
equation for resistance
A
potential difference/current
7
Q
what factors affect potential difference?
A
material of the wire
length of the wire
temperature of the wire
cross sectional area of the wire
8
Q
what is power?
A
power is the rate at which energy is transferred from one form to another
9
Q
equation for power?(not in formulae booklet)
A
power=energy/time
power=work done/time
10
Q
what is a kilowatt-hour?
A
it is 100W for 3600s and is therefor 3 600 000 J
