Answer:[tex]h=\dfrac{kL^2}{8mg}[/tex]
Step-by-step explanation:
Given
Mass of ball is M is dropped from a height h
spring constant is k
Here we can use conservation of energy
Mass has a Potential energy of E=mgh
and when it falls on the spring then it compresses it a length of 0.5 L
Now potential energy is converted into Elastic potential energy and then spring unleashes this energy to the mass and again provide kinetic energy to mass to move upward .
In this way energy is conserved. So, mass must move to an initial height h
[tex]mgh=\frac{1}{2}k(\frac{L}{2})^2[/tex]
[tex]h=\dfrac{kL^2}{8mg}[/tex]
considering [tex]h >> 0.5L[/tex]