Question

If a ladder weighing $250\, N$ is placed against a smooth vertical wall having coefficient of friction between it and floor is $0.3$, then what is the maximum force of friction available at the point of contact between the ladder and the floor?

• A. 75 N
• B. 50 N
• C. 35 N
• D. 25 N

Answer 1

Answer: (A)

75 N

Answer 2

The free body diagram showing the situation is as below.
$R$ is the reaction of the floor on the ladder, $w$ the weight of ladder

Also $R=w=250\,N$ .
Given, $\mu =0.3$
$\therefore F=0.3\times 250=75\,N$ .