Question

The commercial unit of power is kWh, which is equal to:

• A. $1.3\times$ ${10}^5\text{joules}$
• B. $3.6\times$ ${10}^6\text{joules}$​
• C. $3.6\times$ ${10}^5\text{joules}$​
• D. $1.3\times$ ${10}^6\text{joules}$​

Answer 1

The correct option is B $3.6\times$ ${10}^6\text{joules}$​

$\text{1 kWh}$ is the energy used for one hour at the rate of $1000{\text{J s}}^{-1}$.
So, $1\text{kWh}=1000{\text{J s}}^{-1}\times 3600\text{seconds}$
$1\text{kWh}=3.6\times {10}^6\text{joules}$​