Q. A body stars from rest and falls vertically from a height of 19.6m. If $g = 9.8ms^{- 2}$, then the time taken by the body to fall through the last metre of its fall, is
A) 2.00 s
B) 0.05 s
C) 0.45 s
D) 1.95 s
Explanation
(b) $\mathrm{\Delta}t = \sqrt{\frac{2 \times 19.6}{9.8}}s - \sqrt{\frac{2 \times 18.6}{9.8}}s = 2 - 1.95 = 0.05$s
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.