Question

What is the commercial unit of electrical energy ? Convert it into joule.

Answer 1

The commercial unit of energy is kilo-Watt-hour $\left(kWh\right)$

it is used in daily life because SI unit 'joule' is too small to express very large quantities of energy.

1 kWh in joule :

$1kWh=1kW\times 1h$

$=1000W\times 1h$

$=1000J{s}^{-1}\times 3600s$

$1kWh=3600000J$

$1kWh=3.6\times {10}^{6}J$

1 kWh in joule can be expressed as $3.6\times {10}^{6}J$