8.11 Electrical energy and power Flashcards
1
Q
What is power?
A
Power is the rate at which energy is transformed.
2
Q
What is the Si unit of power?
A
The SI unit of power is the watt (W).
3
Q
Electrical power equation
A
power = p.d. * current
P = VI
4
Q
Calculating electrical energy
A
energy transformed = power * time taken
energy transformed = p.d. * current* time taken
E = VIt
5
Q
The kilowatt- hour
A
ONe kilowatt hour is the energy supplied when an appliance of power 1 kW is used for 1 hour.
6
Q
kWh in joules
A
1kWh= 3 600 000 J
