Let the velocity of 2nd fragment is v then by conservation of linear momentum
10(103)i^=(10)(10j^)+10v
⇒v=103i^−10j^
∣v∣=300+100=400=20ms−1.
A ball of mass 10 kg moving with a velocity 10√3ms^-1 along the x -axis, hits another ball of mass 20 kg which is at rest. After the collision, first…
JEE Main 2021 — Physics Mechanics
2021integermedium
A ball of mass 10kg moving with a velocity 103ms−1 along the x -axis, hits another ball of mass 20kg which is at rest. After the collision, first ball comes to rest while the second ball disintegrates into two equal pieces. One piece starts moving along y -axis with a speed of 10ms−1. The second piece starts moving at an angle of 30∘ with respect to the x -axis. The velocity of the ball moving at 30∘ with x -axis is xms−1. The configuration of pieces after the collision is shown in the figure below. The value of x to the nearest integer is
Official previous-year question
Held on 18 Mar 2021 · Verified 6 Jul 2026.
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