By energy conservation
21⋅LYA⋅x2=21mv2
0.10.5×109×10−6×(0.04)2=100020v2
∴v2=400
v=20ms−1
JEE Main 2021 — Physics Mechanics
A stone of mass 20g is projected from a rubber catapult of length 0.1m and area of cross section 10−6m2 stretched by an amount 0.04m. The velocity of the projected stone is ms−1. (Young's modulus of rubber =0.5×109Nm−2)
Held on 27 Jul 2021 · Verified 6 Jul 2026.
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