Question

a ball is dropped from the top of a cliff reaches the ground in 20 seconds what is height of cliff and with but velocity ball hits the ground.

Answer 1

h = ut + 1/2gt²

h = 0 × 20 + 1/2 × 9.8 × 20 × 20

h = 98 × 20

h = 1960m

2gs = v² - u²

v² - 0 = 2×9.8×1960

v² = 38416

v = 196m/s

Answer 2

Answer:

Explanation:

U =0,as ball was dropped

T=20s

T= root over 2h/g

From the above

H=2000m

V=root over 2gh

So we get

V=20m/s