The radius of a body moving in a circle with constant angular velocity is given by r = 4t^2, with respect to time. What is the magnitude of the tangential velocity at t = 2s, if the angular velocity is 7 rad/s?

The radius of a body moving in a circle with constant angular velocity is given by r = 4t^2, with respect to time. What is the magnitude of the tangential velocity at t = 2s, if the angular velocity is 7 rad/s?
 
(a) 112
 
(b) 113
 
(c) 56
 
(d) 28
 
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This key question is from Non-Uniform Circular Motion in division Laws of Motion of Physics – Class 11
Select the correct answer from above options 
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