#### Question

An electric heater is rated at 2 kW. Electrical energy costs Rs 4 per kWh. What is the cost of using the heater for 3 hours?

(a) Rs 12

(b) Rs 24

(c) Rs 36

(d) Rs 48

#### Solution

(b) Rs. 24

Electrical energy consumed in three hours = *P* x *t* = 2 kW x 3 hour = 6 kWh

Unit cost = Rs. 4 per kWh

Therefore, the cost of energy used for three hours = 4 x 6 = Rs. 24

Is there an error in this question or solution?

Solution An Electric Heater is Rated at 2 Kw. Electrical Energy Costs Rs 4 per Kwh. What is the Cost of Using the Heater for 3 Hours? (A) Rs 12 (B) Rs 24 (C) Rs 36 (D) Rs 48 Concept: Electric Power.