Q6 of 149 Page 195

A disc of radius 10 cm is rotating about its axis at an angular speed of 20 rad/s, Find the linear speed of

(a) a point on the rim,


(b) the middle point of a radius.


Given –


Radius of disc = 10 cm = 0.1 m


Angular velocity = 20 rad/s


(a) Now, the linear velocity of the rim is given by -



(b) To calculate linear velocity at the middle of the radius, divide the above equation by 2 we get-


Linear velocity at the middle of radius –



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