Question

Give S.I. unit and commercial unit of energy

Answer 1

Commercial Unit of Energy. The SI unit joule is too small to express very large quantities of energy. Hence we use a bigger unit called kilowatt hour (kWh) to express energy. $1kWh$ is the amount of energy consumed by an electrical gadget in one hour at the rate of $1000J/s$ or $1kW.$

Commercial Unit Of Energy $=kWh$

SI Unit Of Energy = Joule (J)

$1kWh=1kW\times 1h$

$=>1000W\times 3600s$

1 watt - second = 1 joule

$1kWh=3600000J$