Answer to Question #130605 in Physics for amna

Question

What are scalars and what are vectors? Explain in detail along with difference. Also explain two different vector quantities answering the question why do we need to represent these quantities with vectors?

Answer 1

Scalars are quantities that have magnitude only. Vectors are quantities that have direction and magnitude.

For example, speed is a scalar because it only tells us how quickly an object moves no matter where and at what angle. Electric charge is a scalar because it only has magnitude. The same about mass and volume.

Force is a vector because it can be applied at some angle to a body. Magnetic field is a vector because it has north and south poles, and the way it interacts with permanent magnets or wires with electric current depends on the position of the field relative to the object.

Thus, we need to define how we are going to describe force or the field, and that is why we introduced the concept of vector quantities.