Two persns each of mass m are standing at the two extremes of a railroad car of mas M resting on a smooth track figure. The person on left jumps to the left with a horizontal speed u with respect to the state f the cr before the jump. Threafter, the other person jumps to the right, again with the same horizontl speed u with respect to teg state of the car before his jump. Find the vellcity of the car after both the person hae jumped off.