Answer:
The frictional torque is 
Explanation:
From the question we are told that
The mass attached to one end the string is 
The mass attached to the other end of the string is 
The radius of the disk is 
At equilibrium the tension on the string due to the first mass is mathematically represented as

substituting values


At equilibrium the tension on the string due to the mass is mathematically represented as



The frictional torque that must be exerted is mathematically represented as

substituting values


The 26th is Fe(iron) and the 50th is Sn(tin)
Explanation:
Since, it is given that the magnet drops and falls lengthwise towards the canter of the ring. As a result, change in magnetic flux will occur which tends to induce an electric current in the ring.
Therefore, a magnetic field is also produced by the ring itself which will actually oppose or repel the magnet.
Thus, we can conclude that the falling magnet be repelled by the ring due to the magnetic interaction of the magnet and the ring.
Your answer is correct. No problem and Have a nice day