Electrical Energy Calculations

Dean uses rice cooker which has power rating of 2.2kW twice a day. The period for each time he uses the rice cooker is 15 minutes. How much electrical energy is used in kWh?

• 1.10kWh

• 0.67kWh

• 0.55kWh

• 0.27kWh

Jefri just finished watching television with the power rating 180W. The electrical energy used by the television is 0.27kWh. How many hours did Jefri watch the television?

• 1 hour

• 1.5 hours

• 2 hours

• 3 hours

Which of the following lamps has the highest energy efficiency?

• Compact fluorescent lamp

• halogen lamp

• Incandescent lamp

• LED lamp

Tags

NGSS.MS-PS3-3

What is the unit for power?

• Ampere

• Watt

• Kilowatt hour

• Voltage

A 200W electric keetle is used to heat up water for 15 minutes. How much electrical energy is used?

• 0/03kWj

• 0.04kWj

• 0.05kWj

• 0.06kWj

Tags

NGSS.HS-PS3-1

A 2000W vacuum is used for 0.5hours. How long will it takes a 100 W immersion heater to use the same amount of electrical energy?

• 5 hours

• 10 hours

• 15 hours

• 20 hours

If the cost 1kWh of electricity is RM0.30, what is the cost of using a 1.5kW oven for 4 hours?

• RM1.80

• RM2.50

• RM2.20

• RM3.20