Question

A rocket, initially at rest on the ground, accelerates straight upward from rest with constant acceleration 44.1 m/ s 2 . The acceleration period lasts for time 7.00 s until the fuel is exhausted. After that, the rocket is in free fall.

Answer 1

acceleration of rocket is

`a = 44.1 m/s^2`

time taken by rocket

`t = 7 s`

so the distance covered by rocket will be

`d = (1)/(2)at^2`

`d = (1)/(2)*44.1 * 7^2`

`d = 1080.45 m`

speed of the rocket

`v = v_i + at`

`v = 0 + 44.1 * 7 = 308.7 m/s`

now the maximum height it will reach from this is given by

`v_f^2 - v_i^2 = 2 a d`

`0 - 308.7^2 = - 2* 9.8 * d`

`d = 4862 m`

so the total height of rocket will be

`H = 1080.45 + 4862 = 5942.5 m`