Question

Why is speed not considered as a vector quantity?

Answer 1

Speed is considered to be a scalar quantity as it is associated only with the magnitude. Velocity is considered to be a vector quantity as it is associated with both magnitude and direction. The magnitude of speed and velocity both are same. Direction is an important concern here.

Speed is the rate at which an object covers a specified distance. It is a scalar quantity since direction is not necessary. For example, if a person runs 2 kilometers in an hour, his speed is 2 km per hr. It does not matter if he runs on a straight road or on a circular path.

In short speed is not a vector quantity because it has ONLY MAGNITUDE and NO DIRECTION.

Hope this helps :)