Q. In the above question, the percentage increase in the time of flight of the projectile will be
A) 5%
B) 10%
C) 15%
D) 20%
Explanation
(a) Time of flight, $T = \frac{2u\sin\theta}{g}$
$\therefore\ \ dT = \frac{2du\sin\theta}{g}
$Now, $\therefore\ \ \frac{dT}{T} = \frac{du}{u} = \frac{1}{20}$
$\therefore\%$ increase in $T = \frac{dT}{T} \times 100$
$= \frac{1}{20} \times 100 = 5\%$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.