3NT Chapter 4 Electricity Part III

3NT Chapter 4 Electricity Part III

Multiple Choice

What does power mean?

• Joules transferred per second
• Electron flow per second
• Speed of electrons
• Electron energy

Multiple Choice

kWh stand for

• kilowestohm

• kilometwer

• kilowatt hour

Multiple Choice

What is the SI unit of power?

• Ampere (A)
• Volts (V)
• Joule (J)
• Watt (W)

Multiple Choice

Which of the following is the amount of energy used per unit time?

• power
• work done
• electrical energy

Multiple Choice

An air-con, rated 1.8 kW 240 V, is switched on for 10 minutes. Calculate the energy used.

• 1 080 000 J

• 144 000 J

• 2400 J

• 18 J

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

Calculate the electrical energy used by bulb X in 2 minutes.

• 12 J

• 24 J

• 1440 J

• 720 J

Multiple Choice

Calculate the power of bulb X.

• 2 W

• 6 W

• 8 W

• 12 W

Multiple Choice

A space heater plugged into a 120 V outlet carries a current of 12.5 amps. The heater is run for 4 hours. How much energy is used by this heater?

• 6000 kWh

• 6 kWh

• 38.4 kWh

• 2.4 kWh

Fill in the Blanks

Fill in the Blanks

Multiple Choice

An air conditioner has a power rating of 1200 W. How much energy does it consume in 8 hours?

• 0.15 kWh

• 150 kWh

• 9600 kWh

• 9.6 kWh

Multiple Choice

An air conditioner has a power rating of 1200 W. Assume that each unit costs 24 cents, what is the cost of using the air conditioner for 8 hours?

• $0

  $0.036

• $36

• $2304

• $2.30

Multiple Choice

If you have 26 light bulbs in your home, each 60 watts, how much does it cost to operate them, on average, for 2.5 hours a day, for a month? The cost of electrical energy from the utility company is $0.100496.

• $391.93

• $11,578.03

• $15.07

• $11.75

Multiple Choice

How much does it cost to operate a TV for a month if the TV uses 110 V in a 0.33 amp circuit and is operated for 6 hours a day. The cost per kWH is $0.08112

• $530.04

• $4.87

• $0.02

• $0.53