• 5.3: electrical power and potential difference • 5.4: electric currents and electrical transfers • 5.5: appliances and efficiency
|
Created by Farha Idrees
over 6 years ago
|
|
Close
|
|
Created by Farha Idrees
over 6 years ago
|
|
define power rating
1 Watt, W =
Give the formula for power
A 40W light bulb is switched on for 30 mins. Calculate the energy it transfers.
Give the formula for power, using current
Calculate the normal current through a 500W , 230V heater + which fuse you need.
Describe how a resistor works
Give the formula for power supplied to a resistor
Give the formula for charge
What happens when charge flows through a resistor?
Give the formula for energy transferred to a component.
What is the energy from the battery transferred to?
Give the formula for energy
How is the efficiency of a device calculated?
efficiency =
A 230V, 12A electric motor, has an efficiency of 60%, calculate the:
a) power supplied to it
b) output
c) energy wasted
