A simple pendulum, made of a string of length l and a bob of mass m, is released from a small angle _{0}. It strikes a block of mass M, kept on a horizontal surface at its lowest point of oscillations, elastically. It bounces back and goes up to an angle _{1}. Then M is given by
a. 

b. 

c. 

d. 
m 
A simple pendulum, made of a string of length l and a bob of mass m, is released from a small angle _{0}. It strikes a block of mass M, kept on a horizontal surface at its lowest point of oscillations, elastically. It bounces back and goes up to an angle _{1}. Then M is given by
a. 

b. 

c. 

d. 
m 
Before collision After collision
v= v_{1 = }
By momentum conservation
m = MV_{m} − m
⇒ = MV_{m}
and e=1=
( ) = V_{m }…(I)
( ) = MV_{m } … (II)
Dividing
=
By componendo divided
= =
⇒ = ⇒ M= m