Question

Is energy a vector quantity?

Answer 1

As we already know that scalar quantity is defined as the physical quantity that has only magnitude. For example – Mass, distance, volume, electric current, speed, area, temperature, density whereas a vector quantity is defined as the physical quantity that has both magnitude as well as direction. For example – Force, weight, displacement, momentum, acceleration, angular velocity.

Complete answer:
Energy may be defined as the capacity to do work. Energy may exist in potential, electrical, nuclear, or other various forms. Energy is not a vector quantity it is a scalar quantity because it has only magnitude. It does not have any direction.Formula for energy is,
$Energy{\text{ }} = {\text{ }}Power{\text{ }} \times {\text{ }}Time$
The standard unit of energy is $joule$.
As we know that power is the amount of energy transferred or converted per unit time. It is a scalar quantity. The standard unit of power is $Watt$. Time is also a scalar quantity. As it also does not depend on direction.

Hence, energy is not a vector quantity.

Note: Energy is conserved quantity. According to the law of conservation of energy – Energy can neither be created nor be destroyed or also we can say that total energy of an isolated system remains constant . Energy is a scalar quantity because it does not have any direction. Also, the addition and subtraction of the energies are not possible using vector algebra. Therefore, energy is a scalar quantity.