Electric Power Calculations

Electrical power can be calculated using

• Resistance x Voltage
• Voltage x Current 
• Voltage ÷ Current

Watts is the same as...

• Joules per second
• Voltage per second
• Current per second

If the hair dryer and the vacuum cleaner are both on, what is the power used?

• 2600 watts
• 400 watts
• 2200 watts
• 1100 watts

The power of an appliance is...

• the amount of voltage going through it 
• the amount of energy transferred per second
• the amount of charge that passes through per second

The voltage supplied to a circuit is 17 V and the current running through is 10 A. What is the power generated?

• 170 W
• 170 A
• 1.7 V
• 1.7 W

Calculate the electric power of an electrical appliance in which 10 A of current is flowing through a resistor of 2 ohms.
 

• 80 W
• 200 W
• 2.5 A
• 22.5 KJ

What will be the current drawn by an electric bulb of 1000 W when it is connected to a source of 220 V?

• 4.55 A
• 28800 J or 28.8 KJ
• 80 W
• 200 W

If an oven has a power of 2000 W and the voltage is 230 V what fuse is required?

• 3A

• 5A

• 13A

• 8.7A

The current in an appliance is 3 A and the voltage difference is 120 V. How much power is being supplied to the appliance?

• 10000 v
• 220 v
• 420 v
• 360 v

What is the current flowing into a microwave oven that requires 700 W of power if the voltage difference is 120 V?

• 4.3A
• 6.3 A
• 5.83 A
• none