(m1 g−2 T)=m1a−(1) T−m2 g=m2(2a) 2 T−2 m2 g=4 m2a−(2) m1 g−2 m2 g=(m1+4 m2)a a=(8+8)(8−4)g=164 g=4g a=410 m/s2 S=21at2 100.2×2×4=t2 t=0.4sec
The boxes of masses 2 kg and 8 kg are connected by a massless string passing over smooth pulleys. Calculate the time taken by box of mass 8 kg to…
JEE Main 2021 — Physics Mechanics
2021mcqhard
The boxes of masses 2kg and 8kg are connected by a massless string passing over smooth pulleys. Calculate the time taken by box of mass 8kg to strike the ground starting from rest. (g=10ms−2)
Official previous-year question
Held on 27 Aug 2021 · Verified 6 Jul 2026.
Options
- A
0.25s
- B
0.34s
- C
0.2s
- D
0.4s
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