Question

Blocks $A$ and $B$ each have same mass $m=1kg.$ The largest horizontal force $P$ (in newton) Which can be applied to $B$ so that $A$ will not slip up on $B.$ Find value of $P.$ (Neglect any friction)

• A. $10N$
• B. $5N$
• C. $25N$
• D. $15N$

Answer 1

The correct option is D $15N$

In the frame B.

For just slipping,

$\begin{array}{c}\frac{P}{2}\cos \theta =mg\sin \theta \\ P=2mg\tan \theta =2\times 1\times g\tan {37}^{\circ }\\ =2\times 10\times \frac{3}{4}=15N\end{array}$

Ans. (D)