Q. A ball is projected with velocity $u$ at an angle $\alpha$ with horizontal plane. Its speed when it makes an angle $\beta$ with the horizontal is
A) $u\cos\alpha$
B) $\frac{u}{\cos\beta}$
C) $u\cos\alpha\cos\beta$
D) $\frac{u\cos\alpha}{\cos\beta}$
Explanation
(d) $v\ cos\ \beta = u\cos\alpha$
$v = \frac{u\cos\alpha}{\cos\beta}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.