KVPY2019PhysicsMotion in Two Dimensions
A ball is moving uniformly in a circular path of radius 1   m with a time period of 1 . 5   s . If the ball is suddenly stopped at t = 8 . 3   s , the magnitude of the displacement of the ball with respect to its position at t = 0   s is closest to
Options
- A1   m
- B33   m
- C3   m
- D2   m
Correct answer
D. 2   m
Step-by-step solution
Time period of rotation of ball = 1 . 5 s So, in time interval of 7 . 5 s ( = 1 . 5 × 5 ) s ball completes 5 revolutions. Also, ball covers one-fourth of circular path in time 1 . 5 4 = 0 . 375 s So, in remaining 0 . 8 s ( = 8 . 3 - 7 . 5 s ) ball is very near to other end of diameter as shown in the figure. Cleary, displacement of ball is nearly equals to diameter ( = 2 m ) of circular path.