Equation of motion when the mass slides down Mgsinθ−f=Ma⇒10−f=6(M=2 kg,a=3 m/s2,θ=30∘ given )∴f=4 N { Equation of motion when the block is } pushed up Let the external force required to take the block up the plane with same acceleration be F F−Mgsinθ−f=Ma⇒F−10−4=6F=20 N 
A body of mass 2 ~kg slides down with an acceleration of 3 ~m / s^2 on a rough inclined plane having a slope of 30°. The external force required to…
JEE Main 2018 — Physics Mechanics
2018mcqeasy
A body of mass 2 kg slides down with an acceleration of 3 m/s2 on a rough inclined plane having a slope of 30∘. The external force required to take the same body up the plane with the same acceleration will be: (g=10 m/s2)
Official previous-year question
Held on 15 Apr 2018 · Verified 6 Jul 2026.
Options
- A
4 N
- B
14 N
- C
6 N
- D
20 N
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