Topic 21 - power in circuits Flashcards
1
Q
what is the equation for power
A
Power = energy transferred / time P = E / T
2
Q
what does p.d. (voltage) tell you in power
A
how much energy each unit of charge transfers
3
Q
what does current tell you in power
A
how much charge passes per unit time
4
Q
what is the equation to work out power in an appliance
A
Electrical power = current x voltage
P = I x V
5
Q
how do you work out the power if you don’t know the voltage
A
P = (I)2 x R Power = current x resistance
