Q. A packet of weight $w$ is dropped with the help of a parachute and on striking the ground comes to rest with retardation equal to twice the acceleration due to gravity. What is the force exerted on the ground?
A) $w$
B) 2$\ w$
C) 3$\ w$
D) 4$\ w$
Explanation
(c) Mass of the packet $M = w/g$
For packet $F - w = Ma$
or $F - w = \left( \frac{w}{g} \right) \times 2g$
or $F = 3w$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.