Headline Clickable. Whether raw or cooked, food can be chock-full of dangerous bacteria long before you can smell it. Perishable food (like chicken and other meats) should be tossed if left out at room temperature more than two hours (much less if in a warm room).
Catapult physics is basically the use of stored energy to hurl a projectile (the payload), without the use of an explosive. The three primary energy storage mechanisms are tension, torsion, and gravity.
CHRISTMAS STEM ACTIVITY SIMPLE CATAPULT. Making a catapult is a great STEM activity. A catapult uses math, engineering, and science in a very fun way. You could begin your activity by checking out some medieval catapults to see what they were originally used for. A catapult is a simple machine designed that uses a lever. This is one of our favorite quick Christmas projects.