A massless platform is kept on a light elastic spring as shown in figure. When a small stone of mass 0.1 kg is dropped on the pan from a height of 0.24 m, the spring compresses by 0.01m. From what height should the stone be droppped to cause a compression of 0.04m in the spring ?

Explanation

By conservation of mechanical energy `mg(h + y ) = 1/2 Ky^(2)`
h = height of particle,
y = compression of the spring
As here particle and spring remain same
`(h_(1) + y_(1))/(h_(2) + y_(2)) = (y_(1))/(y_(2))^(2) , (0.24 + 0.01)/(h_(2) + 0.04) = (0.01/0.04)^(2),
` h_(2) = 3.96 m`.