incorrect calculator?

westerndragon76

I believe that this calculator generates answers assuming that the only force acting on a falling object after it has encountered a stopping surface is the force of the stopping surface. The calculator needs to factor in gravity throughout the whole fall. Would someone else please verify?
http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html
Click Mechanics, work-energy principle, and then impact force of falling object, and "Since you know velocity, mass, and kinetic energy, can you predict the force of impact?"
Example numbers:
m=50kg, h=10m, d=5m
stopping force should be about 1480N, but the calculator is saying 980N.

Gokul43201

Read the little note at the bottom of that page.

That should take care of your problem (you probably should use d=5, h=5 to describe the situation I think you have in mind). If not for this disclaimer, the calculation would be, as you point out, wrong for the general case where d is not necessarily small compared to h.

westerndragon76

I didn't take time to read that disclaimer carefully. Thanks for the quick answer!

arildno

It is not a disclaimer, it is a caveat.