# Science Fair, pressure to break a bone

1. Jan 3, 2010

### Tantastic

1. The problem statement, all variables and given/known data

Okay, basically I had a bone in ballistic gels, and I dropped a hexagon (6 sided) weight with the measurements of 1 and 1/2 inches per side from 1 feet, 1 1/2 feet and 2 feet on the ballistic gel enclosed bone. Basically I will need a formula to calculate the psi that he bone experienced.

Edit: I calculated the area of the weight to be 13 1/2 square inches, but please double check this.

According to http://hyperphysics.phy-astr.gsu.edu/hbase/flobi.html , the N (Newton?) is 1599, can we convert it to PSI?

2. Relevant equations

How much PSI did the dropping weight cause on the bone?

3. The attempt at a solution

I tried to find a formula to calculate it, but was not really sucessful.

Edit: Okay, so the surface area is 13.5 square inches.. i do not know what formular to use to calculate PSI from this point.

Last edited: Jan 3, 2010
2. Jan 3, 2010

### ideasrule

You can't calculate it. If the bone is stiff and doesn't bend a lot, it would exert a huge force; if it does bend a lot, it would exert a small force. You really need to have something push down on the bone with its weight rather than dropping something and hoping to calculate pressure that way.

3. Jan 4, 2010

### danielatha4

pounds x 4.4 = Newtons

1599/4.4 = pounds

Pounds/Area(in^2) = psi