Question

A stone is thrown vertically upwards with the speed of 20m/so. How high Will it go before it begins to fall? (g=9.8m/s)

Answer 1

Explanation:

v^2-u^2 = 2gs

so 400= 2*9.8*s

s= 200/9.8= 20.4 m

Answer 2

Answer:

20.41 m

Explanation:

Given :

Initial velocity u = 20 m / sec

At top point final velocity v = 0 m / sec

Acceleration due to gravity g = 9.8 m / sec²

We have to find height h :

Using third equation :

v² = u² - 2 g h

= > h = ( v² - u² ) / - 2 g

Putting values here we get :

= > h = ( 0² - 20² ) / - 2 × 9.8

= > h = - 400 / - 19.6 m

= > h = 20.41 m

Hence we get required answer!