Question

Give a specific example of a vector quantity. Explain why this type of quantity would be used to describe this event.

Answer 1

Answer:

Velocity

Explanation:

In physics, there are two types of quantity:

- Scalar quantity: these quantities have a magnitude only, so they don't have a direction. Examples of scalar quantities are mass, temperature, time...

- Vector quantity: these quantities have both a magnitude and a direction. Example of vector quantities are velocity, acceleration, force...

An example of vector quantity is velocity. Velocity is defined as

$v=\frac{\Delta x}{\Delta t}$

where

$\Delta x$ is the displacement of an object, which is a vector connecting its initial position to its final position of motion

$\Delta t$ is the time elapsed

Therefore, velocity has a magnitude and a direction (which is the same as the direction of the displacement). This quantity is used in daily life in many situations, for example when we drive in a car, it is useful to know the velocity at which the car is going.