Question

A ball is projected horizontally from the top of the tower of height 100m with a velocity of 5m/s calculate the time taken by the ball to reach the ground.

Answer 1

$T=\sqrt{\frac{2h}{g}}$

$T=\sqrt{\frac{2*100}{5}}$

$T=\sqrt{40} =2\sqrt{10} sec$

Answer 2

Hey Friend,

◆ Answer-
t = 4 s

◆ Explanation-
# Given-
h = 100 m
u = 5 m/s

# Solution-
Using Newton's 2nd law of motion-
s = ut + 1/2 at^2

For falling body, s = h, a = g,
h = ut + 1/2 gt^2
100 = 5t + 1/2 × 10 × t^2
100 = 5t + 5t^2
t (t+1) = 20

Solving this ,
t = 4 s

Therefore, time taken by ball to reach the ground is 4 s .

Hope this helps...