Living With Electricity Part 1 - Electrical Power and Energy

​Physics Secondary 4
Living With Electricity PART 1

Electrical Power

Multiple Choice

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

Multiple Choice

Electrical power can be calculated using

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

Multiple Choice

Watts is the same as...

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

Multiple Choice

Which of the following equations cannot be used to calculate electrical power?

• $$P\ =\ VI$$

• $$P\ =\ I^2R$$

• $$P\ =\ \frac{V^2\ }{R}$$

• $$P\ =\ \frac{V}{I}$$

Multiple Choice

Which appliance transfers the most energy per second? 

• Clock
• Lamp
• Desktop Computer
• Iron

Multiple Choice

Calculate the energy consumed by a heater of 350W in 7 hours of working.

• 50 kWh

• 50 Wh

• 2450 W

• 2,45 kWh

Multiple Choice

A water heater states 220 V / 5A. If it is used for 1 hour, find the total electrical energy needed for this process?

• 1.1 KJ

• 66 KJ

• 1 584 KJ

• 3960 KJ

Multiple Choice

A toaster, rated 1500 W 240 V, is switched on for 15 minutes. Calculate the energy used.

• 3600 J

• 22 500 J

• 216 000 J

• 1 350 000 J

Multiple Choice

How much energy is converted in a resistor of 5.0 Ω carrying a current of 2.0 A for 10 seconds?

• 4.0 J

• 25 J

• 100 J

• 200 J