Answer:
Option A
Explanation:
For elastic collision
Pbefore collision =Pafter collsion
mv=mvA+m2vB
2v=2vA+2vB .........(i)
Now, coefffficent of restitution,
e=vB−vAuA−vB
Here uB = 0 ( particle at rest) and for elastic collisione= 1
∴ 1=vB−vAv⇒v=vB−vA .............(ii)
From Eq .(i) and Eq .(ii)
vA=v3 and vB=4v3
Hence, λAλB=(hmVA)hm2VB=VB2VA=4/32/3=2