Question

The number of Joules contained in \[1{\text{ }}kWh\]
(A) $36 \times {10^2}$
(B) $36 \times {10^3}$
(C) $36 \times {10^4}$
(D) $3.6 \times {10^6}$

Answer 1

Hint:Here is to corner \[kWh\] to you here \[1\] kilowatt how is a measure of how much energy using it is a unit of measurement that equals the amount of energy.
A joule is a derived unit of energy in the \[SI\] units. It is equal to the energy period of an object when a force of one newton acts on the object in the direction of the force motion.

Complete step by step answer:
Joule can be written as a unit of energy
\[kWh\] is also the unit of energy
\[1kW{\text{ }} = {\text{ }}1000W{\text{ }}and{\text{ }}1hr{\text{ }} = 3600s\]
\[\begin{array}{*{20}{l}}
{1kWh{\text{ }} = {\text{ }}1000{\text{ }}Wh} \\
{\;\;\;\;\;\;\;\;\;\;\; = 1000{\text{ }} \times {\text{ }}3600{\text{ }}Ws} \\
{\;\;\;\;\;\;\;\;\;\;\;\; = 3.6 \times 10\;Ws}
\end{array}\]
Now Ws can be written as J, so
\[{\text{ }}1{\text{ }}kWh{\text{ }} = {\text{ }}3.6 \times {\text{ }}10{\text{ }}J\]
So option D is the correct answer. $3.6 \times {10^6}J$

Note:Here Joules is a unit of work and energy in \[SI\] the system also \[kWh\] is unit of work then we can convert them, but we have to know about their definitions, if we get to know what about what mean then we can solve this. Here as we know Watt second is similar to Joule so we have converted \[1{\text{ }}kWh{\text{ }}to{\text{ }}1{\text{ }}Ws\] then get to Joule conversion.