Q. A particle is thrown vertically upwards. If it velocity at half of the maximum height is $10\ m/sec$, then maximum height attained by it is (Take $g = 10\ m/\sec^{2}\ $)

A) $8\ m$
B) $10\ m$
C) $12\ m$
D) $16\ m$
Explanation

(b) Let particle thrown with velocity $u$ and its maximum height is $H$ then $H = \frac{u^{2}}{2g}$
When particle is at height $H/2$, then its speed is $10\ m/s$
From equation $v^{2} = u^{2} - 2gh$
$(10)^{2} = u^{2} - 2g\left( \frac{H}{2} \right) = u^{2} - 2g\frac{u^{2}}{4g}\ \Rightarrow u^{2} = 200$
Maximum height $\Rightarrow H = \frac{u^{2}}{2g} = \frac{200}{2 \times 10} = 10\ m$

Dr. Abubacker
Reviewed by Dr. Abubacker

Physics Educator & NEET/JEE Specialist

Ph.D. in Physics with 19+ years of teaching experience.