Laws Of Motion Question 406
Question: A boy of mass m is sliding down a vertical pole by pressing it with a horizontal force F. If $ \mu $ is the coefficient of friction between his palms and the pole, the acceleration with which he slides down is
Options:
A) $ g $
B) $ \frac{\mu F}{m} $
C) $ g+\frac{\mu F}{m} $
D) $ g-\frac{\mu F}{m} $
Show Answer
Answer:
Correct Answer: D
Solution:
Here, normal contact force $ N=F $ and friction force, $ f=\mu N $
So the free body diagram of boy is as shown adjacent in the above figure.
Now, $ ma=mg-f $
$ \Rightarrow $ $ a=g-\frac{\mu F}{m} $
