Question

In: Physics

Q1:  Find the final angular velocity if a grinding wheel starts from rest and accelerates at 2...

Q1:  Find the final angular velocity if a grinding wheel starts from rest and accelerates at 2 rad/s^2.


Q2:  If the grinding wheel has a mass of 60kg:

a) Find its rotational inertia.

b) Find the torque that produces the acceleration.

c) Find angular momentum at the instant it has rotated for 8s.


I am pretty much lost. Any help will be greatly appreciated.

Solutions

Expert Solution

Q1) wo = initial angular velocity = 0

      a = angular acceleration = 2 rad/s^2

      w = final angular velocity

   

Using fromula , W = wo +at = 2*t


Q2) M = mass = 60 kg

         

a) I = rotatinal inertia = MR^2/2   ,    where R = radius

                                     = 30R^2


b) T = trouqe = I*a = (MR^2/2 )*2

                               = MR^2

                              = 60 R2


c) at t= 8s , w = 2t = 2*8 = 16 rad/s

     angular mometum = I*w = (MR^2/2)*16   = 8MR^2 = 480R^2





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