Q. Two projectiles A and B thrown with speed in the ratio $1:\sqrt{2}$ acquired the same heights. If A is thrown at an angle of $45{^\circ}$ with the horizontal, the angle of projection of B will be
A) $0{^\circ}$
B) $60{^\circ}$
C) $30{^\circ}$
D) $45{^\circ}$
Explanation
(c) Given condition $h_{1} = h_{2}$
$u_{1}^{2}\sin^{2}45{^\circ} = u_{2}^{2}\sin^{2}\theta$
$\sin^{2}\theta = \frac{u_{1}^{2}}{u_{2}^{2}}\sin^{2}45{^\circ}$
$= \frac{1}{2} \bullet \frac{1}{2} = \frac{1}{4}$
$\sin\theta = \frac{1}{2} \Longrightarrow \theta = 30{^\circ}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.