From the conservation of linear momentum,
m1v1+m2v2=m1v3+m2v4
m1v1+(0.5m1)v2=m1(0.5v1)+(0.5m1)v4
0.5v1+0.5v2=0.5v4
v4=v1+v2
v1=v4−v2
JEE Main 2019 — Physics Mechanics
A body of mass m1 moving with an unknown velocity of v1i^, undergoes a collinear collision with a body of mass m2 moving with a velocity v2i^. After the collision, m1 and m2 move with velocities of v3i^ and v4i^, respectively. If m2=0.5m1 and v3=0.5v1, then v1 is:
Held on 8 Apr 2019 · Verified 6 Jul 2026.
v4−4v2
v4−2v2
v4+v2
v4−v2
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