Question

The practical unit for the measurement of electric power is:

• A. watt
• B. kilowatt
• C. kilowatt hour
• D. horse power

Answer 1

The correct option is A watt

• SI unit of power is $J/s\left(watt\right).$
• Watt can be represented as $kilowatt({10}^3$watt).
• Kilowatt hour is unit of energy (or watt sec, Kilowatt can be changed to watt and hour to sec) so this is unit of energy.
• Horsepower is similarly another unit of power. But it is not very convenient to use since we are using the SI units of energy (joules) and time (seconds) to calculate power. We will have to divide the result by $746$ to obtain power in Horsepower. $(\because 1HP=746W)$

So, the best possible answer is watt, i.e. option A.