Consider a motor that exerts a constant torque of 25.0 nâ‹…m to a horizontal platform whose moment of inertia is 50.0 kgâ‹…m2. assume that the platform is initially at rest and the torque is applied for 12.0 rotations. neglect friction.

W = 1884J

Explanation:

This question is incomplete. The original question was:

Consider a motor that exerts a constant torque of 25.0 N.m to a horizontal platform whose moment of inertia is 50.0kg.m^2 . Assume that the platform is initially at rest and the torque is applied for 12.0rotations . Neglect friction.

How much work W does the motor do on the platform during this process?  Enter your answer in joules to four significant figures.

The amount of work done by the motor is given by:

Where I = 50kg.m^2 and ωo = rad/s. We need to calculate ωf.

By using kinematics:

But we don't have the acceleration yet. So, we have to calculate it by making a sum of torque:

    =>    

Now we can calculate the final velocity:

Finally, we calculate the total work:

Since the question asked to "Enter your answer in joules to four significant figures.":

W = 1884J

k2s for potassium sulphide