Kinematics Question 485
Question: A car is moving in a circular horizontal track of radius 10 m with a constant speed of 10 m/sec. A plumb bob is suspended from the roof of the car by a light rigid rod of length 1.00 m. The angle made by the rod with track it’s [IIT 1992]
Options:
A) Zero
B) $ 30^{o} $
C) $ 45^{o} $
D) $ 60^{o} $
Show Answer
Answer:
Correct Answer: C
Solution:
$ \tan \theta =\frac{v^{2}/r}{g}=\frac{v^{2}}{rg} $
$ \theta ={{\tan }^{-1}}( \frac{v^{2}}{rg} ) $
$ ={{\tan }^{-1}}( \frac{10\times 10}{10\times 10} ) $
$ \theta ={{\tan }^{-1}}(1)=45{}^\circ $