Question

An electric heater of power $3kW$ is used for $10h$. How much energy does it consume? Express your answer in joule.

• A. $1.08\times {10}^5$
• B. $1.08\times {10}^8$
• C. $1.08\times {10}^7$
• D. $1.08\times {10}^3$

Answer 1

The correct option is B $1.08\times {10}^8$

We know that
$Power=work/time$
$Workorenergy=Power\times time$
$Work=3kW\times 10h$
$Energy=30KWh$.
$Energy=30\times {10}^3\times 60\times 60\times =1.08\times {10}^{8}J$.