Electrical energy, power and domestic wiring

Question 1 of 10

State four safety precautions in the use of electricity at home and explain the reason for each.

Question 2 of 10

A 1,000 W heater is used for 4 hours a day for 10 days. At GH₵1.20 per kWh, find the cost.

Question 3 of 10

Find the power dissipated in a 48 Ω resistor connected across 12 V.

Question 4 of 10

The heating element of an electric iron is made of nichrome because it has

Question 5 of 10

Find the power dissipated in a 60 Ω resistor connected across 12 V.

Question 6 of 10

The fuse and switch should be placed in the

Question 7 of 10

A 2 kW appliance used for 5 hours consumes ___ kWh.

Question 8 of 10

A 1 kW appliance used for 2 hours consumes ___ kWh.

Question 9 of 10

Show that P = I²R and P = V²/R, starting from P = IV. A 240 V, 1,200 W iron is used. Find (a) the current, (b) its resistance, (c) the energy used in 15 minutes.

Question 10 of 10

A 3 kW appliance used for 5 hours consumes ___ kWh.