Inertia problems?

Question

1. A stone S is tied to the middle of a string and suspended from one end O. If you give a sharp jerk at P, the other end of the string, then the string will break
Answer : below the stone

2. In the above problem, if we increase the pull at P gradually, the string will break
Answer : above the stone

Please explain the answers. It has got something to do with inertia.

Thanks.

Answer 1

In this case you must consider action forces and reaction (inertia)
1. The answer is correct
The force applied stretches the string that in turn applies force on the stone (the stone resists by its inertia) plus encounter the resistance of the other side of the string.

2. If you do it gradually the string above will experience the weight of the stone plus the tension of the string below.

Answer 2

cylinder has m.o.i Mr^2/2 since u have 2 cylinders involved fused side to side u have the libertry to add in that expression r is radius of the cylinder