Question

Two blocks of masses 10 kg and 4 kg are connected by a spring of negligible mass and placed on a frictionless horizontal surface. An impulse gives a velocity of `14 m//s` to the heavier block in the direction of the lighter block. The velocity of the centre of mass is
A. 30m/s
B. 20m/s
C. 10m/s
D. 5m/s

Answer 1

Correct Answer - C
`v_(CM)=(m_(1)v_(1)+m_(2)v_(2))/(m_(1)+m_(2))=(10xx14+4xx0)/(10+4)=(140)/(14)=10m.//s`