Question

harold threw a baseball 3 meters harold is 2 meters tall. how fast did he throw the ball and how long was it in the air

Answer 1

Answer:

u = 7.74 m/s and t = 1.82 s

Explanation:

Given that,

Harold threw a baseball 3 meters.

Harold is 2 meters tall.

The vertical distance = 3m

The final velocity at the maximum height is  0.

Let u is the initial velocity of the baseball. Using the first equation of motion to find it as follows :

$v^2-u^2=2as$

Here, a = -g

$v^2-u^2=-2gs\\\\u=\sqrt{2gs} \\\\=\sqrt{2\times 10\times 3} \\\\=7.74\ m/s$

He has thrown it with the speed of 7.74 m/s

Let t is the time taken by the ball to fall on the ground.

Harold is 2 meters tall. Using second equation of motion to find it.

u = -7.74 (as downward direction is taken as positive)

$s=ut+\dfrac{1}{2}at^2\\\\2=-7.74t+5t^2\\\\t=1.82\ s$

Hence, this is the required solution.