Science Buddies: "Ask an Expert"

MY DAUGHTER IS DOING A SCIENCE PROJECT ON HOW MUCH PRESSURE IT WILL TAKE TO CRACK AN EGG. HOW WOULD SHE CONVERT THE POUNDS SHE USES TO UNITS OF PRESSURE IS THERE AN INSTRUMENT THAT CAN BE PURCHASED TO HELP HER WITH THIS CONVERSION MY HUSBAND THINKS THAT THEY HAVE THESE AT AUTO PARTS STORES BUT DOESN'T KNOW WHAT THEY ARE CALLED

Perssure is defined as a force per unit area.

Pressure = Force / Area

If your daughter is measuring pounds, that is the Force part of the equation. To measure the Area, do your best to measure the area of contact bettwen the egg and whatever is pushing on the egg. (This is not ideal since an egg is not flat)

If you measure Force in pounds (lb) and Area in inches (in), then Pressure will be in pounds per squared inch (psi).