2 bodies of masses 'm' and '3m', moving with velocities 3v and v respectively along same direction, collide with each other. After collision they stick together and move with a velocity V in the same direction. Then:
A) V=v
B) V=3/2v
C)V=2v
D) V=4/3v
 

Asked by adityaahuja099 | 12th Oct, 2017, 11:39: PM

Expert Answer:

Initial momentum of both bodies m×3v + 3m×v = 6×m×v
 
after collision combined mass is 4×m
 
By conservation of momentum, momentum after collision is 6×m×v
 
so velocity after collision is fraction numerator 6 cross times m cross times v over denominator 4 space cross times space m end fraction space equals space 3 over 2 v

Answered by  | 13th Oct, 2017, 12:04: PM