Question

An electric heater is rated 220v,500w .calculate the electrical energy consumed in 4 hours

Answer 1

Given :

• Voltage of the electric heater = 220 V

• Power of the electric heater = 500 W

To find :

• The electrical energy consumed in 4 hours

Solution :

★ The unit of electrical energy consumed is kWh.

So, firstly we shall convert it from watts into killowatt hours.

As we know,

• 1 kWh = 1000 W

To convert the value from kWh into W divide it by 1000.

→ Power = 500 ÷ 1000

→ Power = 5 ÷ 10

→ Power = 0.5

Therefore, power in killowatt hours = 0.5 kWh

Now, calculating the electrical energy consumed :-

Using formula,

→ Electrical energy = Power × Time

Substituting the given values :-

→ Electrical energy = 0.5 × 4

→ Electrical energy = 5/10 × 4

→ Electrical energy = 1/2 × 4

→ Electrical energy = 2

Therefore, electrical energy consumed by the heater in 4 hours = 2 kWh