Question

Which one of the following is a scalar quantity?
A. Displacement
B. Velocity
C. Acceleration
D. Linear momentum
E. Kinetic energy

Answer 1

Hint: The physical quantities which have certain qualities upon which the identification of scalar or vector quantity depends.

Complete step by step solution:
From the above hint, we can determine the scalar quantity from the given quantities. A scalar quantity is one which has only magnitude and no direction. In other words, we can say that the physical quantity gives us the size or magnitude i.e., units of measurements are attached to only numbers with absence of directional components.
Some of the examples of scalar quantities are: Time, length, area, volume, energy etc.
So, from the given options kinetic energy is a scalar quantity.

Therefore, the answer is option E.

Additional information: Vector quantity depends on not only magnitude but also on the direction. Some of the examples of vector quantities are: displacement, acceleration, velocity etc.

Note: Any random number is not a scalar. For example, number 42 is meaningless unless we mention that 42 is a measurement of something like time or temperature which indicates that we have to be careful while determining any physical quantity as scalar or vector. In other words, we must be careful with magnitude and directions that are responsible for identification of the physical quantity as scalar or vector.