The forces acting on the block are shown below.
Here, N is normal force and box is falling with acceleration a.

From figure, Mg−N=Ma
According to question, N=4Mg
4Mg=M(g−a)
⇒a=43g
A block of mass M placed inside a box descends vertically with acceleration a. The block exerts a force equal to one-fourth of its weight on the floor of the box. The value of ′a′ will be
Held on 29 Jun 2022 · Verified 6 Jul 2026.
g
43g
2g
4g
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