Calculate the speed of impact at the ground

[Karma]

Erik Drops a ball from a height of 15.0m above the ground. After it hits the ground it only bounces back up to a height of 13.5m. Erik Catches it at this point, as it is just about to fall back down.

just need some quick helping steps to get me started on these questions
help would be appreciated thanks.

a>)Calculate the speed of impact at the ground
b>)Calculate the initial speed of the ball as it boucnes off the ground
c>)Calculate the total time that the ball is in the air
d>)At what time does the ball pass a point 3.5m abov the ground

 

[al_201314]

What are the equations you know for linear acceleration?

 

[Karma]

Ok can someone please help me out with the last qeuestion please>

 

[garyljc]

Hint : What will your displacement be ?

 

[arunbg]

Please show your thoughts and working and we'll try our best to help.