Test 6.4 Calculating Cost of Electrical Energy

The electrical energy used by an air conditioner for 2 minutes is 180 kJ. What is the power of this air conditioner in W ? (Power = Energy / time)

• 1500 W

• 1.5 W

• 90 W

• 90 000 W

A microwave oven rated 1.2kW, 240 V is connected to a 240 V electricity supply. What is the amount of current that flows through the oven?

• 0.005 A

• 5 A

• 200 A

• 0.2 A

An electric rice cooker rated 800 W, 230 V is switched on for 30 minutes. How much electrical energy is used by the rice cooker?

• 24 kWh

• 24 000 kWh

• 0.4 kWh

• 400 kWh

An electric rice cooker rated 800 W, 230 V is switched on for 30 minutes. What is the cost of energy that is used by the rice cooker if the cost per kWh is 30 cent?

• RM 12 000.00

• RM 120.00

• RM 12.00

• RM 0.12

What is the importance of star rating labelling of an electrical appliance?

• It is important for the buyer to know the price.

• It shows the energy efficiency of the electrical appliance.

• It helps consumer to allocate the suitable amount of time per usage.

• for the buyer to learn more about the brand and model of the appliance.

How many stars in the star rating label of an electrical appliance should be used? (the least star rating should be used)

• 1 star

• 2 stars

• 3 stars

• 4 stars