Question

find out the value of T to reach Ground from a body dropped from 20 metre of height​

Answer 1

Answer:

2 second

Explanation:

Time to reach ground = √2h/g

= √2*20/10

=√4

=2 second

Answer 2

Explanation:

Here, h = 20 m, G = 9.8 m/ second square, t=?, u=0

By Newton's 2nd equation of motion

$h = ut + \frac{1}{2} g {t}^{2} \\ 20 = 0 \times t + \frac{1}{2} \times 9.8 \times {t}^{2} \\ {t}^{2} = \frac{40}{9.8} = 4.08 \\ t = 2.01 \: seconds \: = 2 \: sec$