Question

If the block is pulled by a distance x and left, the block will start oscillating. The value of x, so that at a moment when speed of the block become zero the spring becomes unstretched

Answer 1

Answer:

As the spring is stretched by mg/k due to gravity so it is in eqb. It is stretched again by amplitude mg/k t starts oscillating.

so the max disp upward is mg/k and the block speed is 0 and the spring is unstreched.