buoyancy experiment
Nevaeh Williams,10, uses a hot glue gun to construct a bridge out of popsicle sticks, styrofoam peanuts and dried lasagna pasta May 10, 2012, at Nellis Air Force Base, Nev. The science experiment is used to help students understand buoyancy. (U.S. Air Force photo/Airman 1st Class Jason Couillard)