Solo 189
date:
w
a ballifs gently dropped from a height of rom. if its
velocity increases oniformly at the rate of 10m/s2, with
whor velocity wall pt strike the ground? after what time
will it strike the ground?

Note: Since I could not understand the height it was dropped from I will be using R. You can substitute whatever height in place of R.

Let the up be increasing y and down be decreasing y. We know the acceleration in the y direction which is,

I'm going to call it -g for simplicity.

Now integrating to get velocity,

Notice since the ball was dropped from rest, so the constant of integration is 0.

Integrating once more to get position,

<Since R is the initial height, it is the constant of integration here>

To answer the question for what time will it hit the ground, setting y=0 and solving for t we get:

Now to get the velocity at which it hit the ground, we plug in this value of t into our velocity equation:

Hope this helps!

the answer is 3.1 his answer is wrong mines is right