What is a scalar quantity? Vector quantity? How are these two different?

Answer: Scalar quantity has magnitude but no direction while a vector quantity has both magnitude and direction.

Explanation:

A scalar quantity is a physical quantity that has magnitude but no direction. Examples are

- temperature, measured in Kelvin

- distance, measured in metres

- speed, measured in metres per second

Vector quantity, on the other hand, is a physical quantity that have both magnitude and direction. Examples are:

- velocity, measured in metres per second (m/s)

- force, measured in newton

- displacement, measured in metres