As a vector is having both direction and magnitude, then is it necessary that if anything is having direction and magnitude it is termed as a vector? The rotation of an object is defined by the angle of rotation about the axis and the direction of rotation of the axis. Will it be a rotation of a vector?

Asked by Abhisek | 1 year ago |  155

##### Solution :-

No, A physical quantity which is having both direction and magnitude is not necessarily a vector. For instance, in spite of having direction and magnitude, the current is a scalar quantity. The basic necessity for a physical quantity to fall in a vector category is that it ought to follow the “law of vector addition.”

As the rotation of a body about an axis does not follow the basic necessity to be a vector i.e, it does not follow the “law of vector addition”, so it is not a vector quantity. Although in some cases rotation of a body about an axis by a small angle follows the law of vector addition so it is termed as a vector.

Answered by Pragya Singh | 1 year ago

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