Q. In the first second of its flight, rocket ejects $1/60$ of its mass with a velocity of $2400\ ms^{- 1}$. The acceleration of the rocket is
A) $19.6\ ms^{- 2}$
B) $30.2\ ms^{- 2}$
C) $40\ ms^{- 2}$
D) $49.8\ ms^{- 2}$
Explanation
(c) Acceleration $a = \frac{1}{m}\left( \frac{- dm}{dt} \right)v_{r} = \frac{1}{1}\left( \frac{1}{60} \right) \times 2400 = 40\ ms^{- 2}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.