Physics: A 5.0 kg ball is dropped from a 2.5 m high window. what is the velocity of the ball just before it hits the ground?

if you dont give me a question I can t answer sorry...

A 5.0 kg ball is dropped from a 2.5 m high window.

Ответ:

Gtx014

20.01.2022

Physics

Approximately $7.0\; \rm m \cdot s^{-1}$ .

Assumption: the ball dropped with no initial velocity, and that the air resistance on this ball is negligible.

Explanation:

Assume the air resistance on the ball is negligible. Because of gravity, the ball should accelerate downwards at a constant $g = 9.81 \; \rm m \cdot s^{-2}$ near the surface of the earth.

For an object that is accelerating constantly,

$v^2 - u^2 = 2\, a \, x$ ,

where

is the initial velocity of the object,

is the final velocity of the object.

is its acceleration, and

is its displacement.

In this case, is the same as the change in the ball's height: $x = 2.5\; \rm m$ . By assumption, this ball was dropped with no initial velocity. As a result, u = 0 . Since the ball is accelerating due to gravity, $a = 9.81\; \rm m \cdot s^{-2}$ .