Question

Acceleration which brings change in only direction is called

Answer 1

Accelaration which brings change in only direction is called velocity.

Answer 2

The acceleration which changes due to its magnitude is called linear acceleration whose measurement is done as Change in volocity / time

On the other hand , when body moves in a circle , at every point of the circle it accelerates , But here speed of the body remain constant , So if we find the magnitude of acceleration using linear acceleration , we get zero accelerstion...

But we say as body accelerate at every point on the circle...So this acceleration is due to change in direction not change in magnitude...Such acceleration is called Centripetal acceleration...Which always acts on the center of the circle...

and its magnitude is equal to v^2 / r

where v = speed of the body moving in a circle , r = radius of the circle..