Q.
A body is thrown vertically upwards with velocity $u$. The distance travelled by it in the fifth and the sixth seconds are equal. The velocity $u$ is given by ($g = 9.8\ m/s^{2}$)
A) $24.5\ m/s$
B) $49.0\ m/s$
C) $73.5\ m/s$
D) $98.0\ m/s$
Explanation
(b) The given condition is possible only when body is at its highest position after $5\ seconds$
It means time of ascent $= 5\ sec$
and time of flight $T = \frac{2u}{g} = 10$
$\Rightarrow u = 49\ m/s$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.