A particle is kept at rest at the top of a sphere of diameter 42 m. When disturbed slightly, it slides down. At what height h from the bottom, the particle will leave the sphere
A) 14m
B) 28m
C) 35m
D) 7m
Correct Answer:
C
Solution :
The condition of slipping by particle from top is given by \[\cos \theta =\frac{2}{3}\] From the figure, \[h=r\cos \theta =21\times \frac{2}{3}=14\,m\] Therefore, .the required height at which the particle will leave the the sphere is \[=21+h=21+14=35m\]