Answer:
Energy cannot be changed from one form to another without a loss of usable energy
Explanation:
Second law of thermodynamics states that the total entropy or the randomness of the system remains constant over time. It also states that the net entropy will remain the same or it will increase.
Entropy of a system is given by heat absorbed divided by temperature. It is given by :
So, the correct option is (A) "Energy cannot be changed from one form to another without a loss of usable energy".
Since no external torque is acting on the system you can use the conservation of angular momentum. I derived the final angular speed below and shown my work on how I did it. It’s now just a matter of plugging in the numbers and using correct placement of negative sign for direction of angular velocity. L in the picture stands for angular momentum. Hope it helps
