Question

Two blocks of masses 2 kg and 3 kg are connected
by massless spring and are placed on smooth
surface. If impulse is given to 2 kg block and block
starts moving with velocity 10 m/s in (+ve) -
direction, then velocity of 2 kg block w.r.t centre of
mass is
(1) 4 m/s (+ve) x-direction
(2) 6 m/s (+ve) x-direction
(3) 4 m/s (-x) direction​

Answer 1

Answer:

(2) 6 m/s (+)ve x direction

Answer 2

Answer:

Option 2) 6 m/s (+ve) x-direction.

Explanation:

From the question we will get that the two masses are attached to a string and is connected to each other. so, the velocity of the center of mass will be given as (m1v1+m2v2)/(m1+m2) which is (2*10+3*0)/(2+3) since, the velocity of the second body of mass 2 is given as zero. So, on solving we will get the velocity of the center of mass as 4 m/s in the positive x direction.

So, the velocity of the 2kg block with respect to the center of mass will be given as 10-4 = 6 m/s in the positive x direction.