S1=S2
35t+21(−g)t2=35(t−3)+21(−g)(t−3)2
35t−21gt2=35t−35×3−21g(t2−6t+9)
(35×3)+45=30t
t=30150=5
heighth=35×5−21×10×52
h=175−125=50m
JEE Main 2021 — Physics Mechanics
Two spherical balls having equal masses with radius of 5cm each are thrown upwards along the same vertical direction at an interval of 3s with the same initial velocity of 35ms−1, then these balls collide at a height of _____m,
(take g=10ms−2)
Held on 26 Aug 2021 · Verified 6 Jul 2026.
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