Q. A ball thrown by a boy is caught by another after $2\ sec$ some distance away in the same level. If the angle of projection is $30{^\circ}$, the velocity of projection is
A) $19.6\ m/s$
B) $9.8\ m/s$
C) $14.7\ m/s$
D) None of these
Explanation
(a) $T = \frac{2u\sin\theta}{g} \Rightarrow u = \frac{T \times g}{2\sin\theta} = \frac{2 \times 9.8}{2 \times \sin 30} = 19.6\ m/s$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.