Question

An electric kettle is rated $2.5kW,250V$. What is the cost of running the kettle for two hours at Rs. $5.40$ per unit?

• A. $Rs.17.00$
• B. $Rs.27.00$
• C. $Rs.26.00$
• D. $Rs.16.20$

Answer 1

The correct option is B $Rs.27.00$

The energy, $E$ in kilowatt-hours (kWh) is equal to the power, $P$ in kilowatts (kW), times the time period, $t$ in hours (hr).

That is, $P=kW\times t=2.5kW\times 2=5kWh$.
The cost per $kWh$ is given as Rs. $5.40$.

Hence, the total cost of running the kettle for two hours is given as: $5\times 5.40=Rs.27.00$