
Angular impulse = change in angular momentum
τΔt=ΔL
mg2l×0.01=3ml2ω
ω=2l3g×0.01=2×0.33×10×0.01=0.5rad/sec
Time taken by rod to hit the ground = g2h=102×5=1s
Angle rotated by rod = ωt=0.5×1=0.5rad
JEE Main 2019 — Physics Mechanics
A rectangular solid box of length 0.3m is held horizontally, with one of its sides on the edge of a platform of height 5m . When released, it slips off the table in a very short time τ=0.01s , remaining essentially horizontal. The angle by which it would rotate when it hits the ground will be (in radians) close to:

Held on 8 Apr 2019 · Verified 6 Jul 2026.
0.5
0.3
0.02
0.28
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