Question

A body is thrown vertically upwards and rises to a height of 10 m. The velocity with which the body was thrown upwards is $(g=9.8m/s^2)$

• A. 10 m/s
• B. 20 m/s
• C. 14 m/s
• D. None of these

Answer 1

The correct option is C 14 m/s

Maximum height $h=10m/s$

At maximum height, $v=0$

Let the initial velocity be $u$.

Acceleration $a=-g=-9.8m/s^2$

$\therefore$ $0-u^2=2(-9.8)\left(h\right)$

$⟹u=\sqrt{2gh}=\sqrt{2\times 9.8\times 10}=14m/s$