Two particle A and B start moving due to their mutual interaction only. If at any tiem 't', `vec(a)_(A)` and `vec(a)_(B)` are their respective accelerations, `vec(v)_(A)` and `vec(v)_(B)` are their respective velocities, and upto that time `W_(A)` and `W_(B)` are the work done on A and B respectively by the mutual force, `m_(A)` and `m_(B)` are their masses respectively, then which of the following is alwys correct.

Options

A. `vec(v)_(A) + vec(v)_(B) = 0`
B. `m_(A) vec(v)_(A) + m_(B)vec(v)_(B) = 0`
C. `W_(A) + W_(B) = 0`
D. `vec(a)_(A) + vec(a)_(B) = 0`

Answer

B

Explanation

In the absence of external forces, the linear momentum of the system remains constant.