Two trains are running on parallel tracks., train A is faster than B.There is a box on each train of identical nature. But mass of box in train A is more than that of train B. If box is changed between the trains, what happens to speed of trains?
A.Same
B. A faster
C. B faster
D. none
To determine what happens to the speed of the trains when the boxes are exchanged, we need to consider the concept of momentum.
Momentum is the product of an object's mass and velocity. In this case, both trains have identical boxes, so the only difference between the two trains is their mass.
When the box from train A, which has a greater mass, is exchanged with the box from train B, which has a lesser mass, the total mass of both the trains remains the same. Therefore, the total momentum of the system (the two trains along with the boxes) remains constant.
According to the law of conservation of momentum, in the absence of external forces, the total momentum of a system remains constant.
Since the total momentum of the system is the same, the speed of the trains remains unchanged. Therefore, the correct answer is:
A. Same