A heavy ball being dropped

[miamiheat5]

A heavy ball is dropped into a lake from a height of 30.0m above the water. it hits the water with a certain velocity and continues to sink to the bottom of the lake at this same constant velocity. It reaches the bottom of the lake 10.0s after it was dropped. How deep is the lake.


And the solution i got:


vf^2=vi^2+2ad
vf^2=2(-9.81)(30.0)
vf=24.3m/s


d=vt
=(24.3)(10)
=24.3m deep

 

[chaoseverlasting]

24.3*10=243m