A acorn falls from a tree and hits the ground with a speed of 10 m/s:

Question

- From what height did the acorn fall?
- How long was the acorn in the air?

Answer 1

If the acorn fell from rest,
equate energies
mgh=(1/2)mv²

h=v²/2g
=100/(2*9.8)
=5.1 m

Time
=v/g
=10/9.8
=1.02 s