- #1
Titan97
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Homework Statement
Two identical buggies 1 and 2 of mass ##M## with one man of mass ##m## in each, move without friction due to inertia towards along two parallel rails. When the buggies are opposite to each other, the men exchange positions by jumping in a direction perpendicular to motion of buggy. As a consequence, buggy 1 stops, while buggy 2's velocity becomes v. Find initial velocities ##v_1## nad ##v_2## of buggy 1 and 2.
Homework Equations
Conservation of momentum
The Attempt at a Solution
When the man jumps from buggy one, no force acts on the man+buggy system along horizontal. Since mass changes, velocity changes accordingly to make momentum constant. So,
##(m+M)v_1=Mu_1##
##u_1=(\frac{m}{M}+1)v_1##
This means velocity of buggy increased.
When the second man jumps to buggy one, again no force acts along horizontal. Hence,
##Mu_1=(m+M)u'_1##
But here is the problem. ##u'_1=0##. This means ##u_1=0## which means ##v_1=0##. This is wrong.
What is my mistake?