Question

If angular velocity is constant thent what is tangential acceleration

Answer 1

If angular velocity is constant this means that the body is covering equal angles in equal intervals of time. If the body is covering equal angles then it must covering equal distances in equal time intervals which implies that tangential acceleration is zero.

Answer 2

In a uniform circular motion the speed of the body remains constant whereas the direction of the moving body changes at every point, resulting in change of velocity (velocity has two components speed and direction) and because velocity changes acceleration exists. The direction of acceleration in this case is radial ie tangential component is zero the speed is not varying with time.
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