CGPET 2019 Solved Paper

Given, mass of A=m
Mass of B=2m
According to question, system is released from rest with spring unstretched.
Then, decrease in potential energy of B
= Increase in spring potential energy
⇒∴2mgxm=

1

2

Kxm2 .......(i)
Here, xm= maximum extension,
K= force constant and
g= gravitational acceleration
From Eq. (i)
2mg=

1

2

Kxm
So, maximum extension xm in spring,
⇒ xm=

4mg

K