Chapter 2, Problem 1MC

Which of the following quantities is not a vector quantity?

1. a. velocity
2. b. acceleration
3. c. mass
4. d. force

To determine

The quantities which are not vectors.

Answer to Problem 1MC

Option (c) mass.

Explanation of Solution

Physical quantities can be of two categories, scalars and vectors.

Scalars are those quantities that can be defined fully using their magnitudes. These quantities does not require direction. Few of the examples of scalar quantities are speed, volume and temperature.

Vectors require both magnitude and direction of the quantity to describe it completely. Vector can be represented using an arrow showing the direction of the quantity and the length of the arrow is proportional to the quantity’s magnitude. The examples of vectors include momentum, displacement and electric field.

Conclusion:

The quantity, mass, can be explained completely using just the magnitude of the quantity. So, mass is not a vector quantity. Thus, option (c) is correct.

Velocity has both magnitude and direction. Thus, velocity is a vector quantity. Thus, option (a) is incorrect.

Acceleration needs both magnitude and direction in order to give its complete meaning. Thus, velocity is a vector quantity. Thus, option (b) is incorrect.

Force is a physical quantity with both magnitude and direction. So, force is a vector quantity. Thus, option (d) is incorrect.