Q. A stone thrown upwards, has equation of motion $s = 490t - 49t^{2}.$Then, the maximum height reached by it ,is
A) 24500
B) 12500
C) 12250
D) 25400
Explanation
(c)
Given , $s = 490t - 4.9t^{2}$
$\Rightarrow \ \ \ \frac{ds}{dt} = 490 - 9.8t$
$\ \ \$A stone is reached the maximum height when $\frac{ds}{dt} = 0$
$\Rightarrow \ \ 490 - 9.8t = 0 \Rightarrow t = 50$
$\therefore\$Maximum height at $t = 50$
$\ \ s = 490(50) - 4.9(50)^{2} = 12250$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.