An object with a mass of # 3 kg# is traveling in a circular path of a radius of #7 m#. If the object's angular velocity changes from # 16 Hz# to # 17 Hz# in #5 s#, what torque was applied to the object?

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Answer 1 · 2017-01-12T07:31:09

The torque is #=184.7Nm#

The torque is the rate of change of angular momentum

#tau=(dL)/dt=(d(Iomega))/dt=I(domega)/dt#

The moment of inertia of the object is #I=mr^2#

#=3*7^2= 147 kgm^2#

The rate of change of angular velocity is

#(domega)/dt=(1)/5*2pi#

#=((2pi)/5) rads^(-2)#

So the torque is #tau=147*(2pi)/5 Nm=294/5piNm=184.7Nm#