Question

Two spheres of masses `m and 2m` are separated by distance `d`. A particle of mass `(m)/(5)` is projected straight from `2m` towards `m` with a velocity `v_(0)`. Which of the following statements is correct ?
A. Velocity of the particle decreases constantly
B. Velocity of the particle increase constantly
C. Acceleration of the particle may become momentarily zero
D. The particle never retraces its path

Answer 1

Correct Answer - C
Acceleration between them is zero, where force between `2m and (m)/(5)` is equal to the force between `m and (m)/(5)` or the net force on `(m)/(5)` is zero. Suppose this point is P. Now if velocity `v_(0)` is less than value necessary to cross point P, it will retrace its path otherwise not.