A) both A and R are true and R is the correct explanation of A
B) both A and R ane true but R is not the correct explanation of A
C) A is true but R is false
D) A is false but R is true
Correct Answer: D
Solution :
We know that if a body moves with constant speed on a circular path, it is a uniform circular motion, an acceleration along radius towards centre and has magnitude. \[a={{a}_{r}}=\frac{{{v}^{2}}}{r}=r{{\omega }^{2}}\] This is called central acceleration. So, speed and magnitude of acceleration are constant but their direction are always changing to provide centripetal acceleration by Newtons second law of force, \[F=ma=\frac{m{{v}^{2}}}{r}=mr{{\omega }^{2}}\] This force is called centripetal force and is of constant magnitude but changing direction. Hence assertion is wrong and reason which is, that the direction of velocity vector of a body moving in a circular path is changing is true.You need to login to perform this action.
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