When used as a rocket booster, it is filled with 66 Ibs. of water heated electrically to 504° F. The water cannot boil because it is confined, but its pressure rises to 50 atmospheres (735 Ibs.
Download the Water bottle Rockets PDF(378 Kb ... Making a hole through the cork using a drill, punch or awl is a job for an adult. The rocket launches with little or no warning and can fly ...