Question

A system consists of 2 particles of the same mass. Let one particle be at rest and another particle have an acceleration of “2a”. What would be the acceleration of the centre of mass of the system?

(a) a/4

(b) a/2

(c) a

(d) 2a

I have been asked this question in homework.

The origin of the question is System of Particles topic in section System of Particles and Rotational Motion of Physics – Class 11

Answer 1

The correct choice is (c) a

Best explanation: The acceleration of the centre of mass = (m1*a1 + m2*a2)/(m1 + m2)

m1 = m2 = m

a1 = 0

a2 = 2a

The acceleration of the centre of mass = (m*0 + m*2a) / (m + m)

 = 2ma/2m

 = a.