Conservation of linear momentum
0.1×20=(0.1+1.9)×v
v=1ms−1
Using work energy theorem
Wg=Δk
2×g×1=k−21×2×12
∴k=21J
JEE Main 2020 — Physics Mechanics
A block of mass 1.9kg is at rest at the edge of a table, of height 1 m. A bullet of mass 0.1kg collides with the block and sticks to it. If the velocity of the bullet is 20ms−1 in the horizontal direction just before the collision then the kinetic energy just before the combined system strikes the floor, is [Take g=10ms−2. Assume there is no rotational motion and loss of energy after the collision is negligible.]
Held on 3 Sept 2020 · Verified 6 Jul 2026.
21J
20J
19J
23J
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