A firecracker is fired and it rises to a height of 1000 m then the velocity (in m/s) by which it is released is ____

A firecracker is fired and it rises to a height of

1000 m

then the velocity

(in m / s)

by which it is released is

140

.
Given,
Height,

h = 1000 m

Final velocity,

v = 0

Acceleration due to gravity

g = - 9.8 m / s^{2}

[as a gravitational force acts downwards]
By using the equation of motion,

{\Rightarrow v}^{2} - u^{2} = 2 gh

…..(1) Here

u

is initial velocity

v

is the final velocity

h

is the hight and

g

is the gravitational acceleration.

\Rightarrow u = \sqrt{v^{2} - 2 gh}

\Rightarrow u = \sqrt{0 - 2 \times (- 9.8) \times 1000}

\Rightarrow u = 140 m / s

Therefore, the velocity by which it was released is

140 m / s

A firecracker is fired and it rises to a height of $1000 m$ then the velocity $(in m / s)$ by which it is released is ____