Question

​a body falls from 80m its time of descent is ? [when g=10m/s2]

Answer 1

s=1/2gt²+it
as u=0
80=1/2(10)t²
t²=16
t=4 sec

Answer 2

The time taken to the falling of body is 4 seconds.

To find:

The time of descent of the fallen body.

Given:

The height from the fallen body, h = 80 m

Solution:

The time of descent is the time taken by a ‘free falling’ object to reach the ground downwards.  

The formula required to calculate is$t=\frac{\sqrt{2 \hbar}}{s}$

where h is the “height of the descent” and “g is the gravitational constant”.

G = $10 \mathrm{m} / \mathrm{s}^{2}2$

t = $\frac{\sqrt{2 \mathrm{h}}}{\mathrm{g}}$

t =$\frac{\sqrt{2 \times 80}}{10}$

t = 4 seconds.