Question

A body is describing a circular motion with a speed v when it describes an angle α at the centre the change in the velocity delta v is

Answer 1

$$v_1=v,v_2=v$$

$$\Delta v=|\bold{v_2-v_1}|=\sqrt{v_1^2+v_2^2-2v_1v_2\cos\alpha}$$

$$\Delta v=\sqrt{2v^2(1-\cos\alpha)}$$

$$\Delta v=2v\sin{\frac{\alpha}{2}}$$