Laws Of Motion Question 340
Question: An insect of mass m, starts moving on a rough inclined surface from point A. As the surface is very sticky, the coefficient of friction between the insect and the incline is$ \mu =1 $ . Assume that it can move in any direction, up the incline or down the incline then
Options:
A) The maximum possible acceleration of the insect can be $ 14m/s^{2} $
B) The maximum possible acceleration of the insect can be $ \text{2 }m/s^{2} $
C) the insect can move with a constant velocity
D) the insect cannot move with a constant velocity
Show Answer
Answer:
Correct Answer: C
Solution:
[c] $ mgsin\theta +mg cos \theta =ma $
$ a=g\sin \theta +g\cos \theta =10[ \frac{3}{5}+\frac{4}{5} ]=14m/{{\sec }^{2}} $
$ Iff _{r}=mg\sin \theta $
$ =mg\times \frac{3}{5}=\frac{3mg}{5}<{f _{r\max }} $
$ f _{r}<{f _{r\max }} $
$ \frac{3mg}{5}<\frac{4mg}{5} $
Hence, insect can move with constant velocity.