How Do You Calculate the Time and Speed of a Falling Object?

[aussierad]

Hey guys,
Just wondering if you could please help me decode this question as well as put a little explanation as to how you got that answer. I am really struggling to get the correct calculations

(Take g = 9.8 m.s -2)

A stone is dropped from a height of 51.2 metres from the ground.
(a) How long does it take to reach the ground?
(b) What speed just before it strikes the ground?
(c) How far does it fall during the last second of it's fall?


Thanks!

 

[Doc Al]

Show the calculations that you've been doing and perhaps we can help spot what's going wrong.

You might need to review the Basic Equations of 1-D Kinematics.