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.
Catapults were ancient siege engines that used a simple principle of physics, known as stored energy, to hurl a payload without the need for explosives. The application of sufficient force to an object can change its shape. Elastic objects, such as wood or rope, are able to store potential energy when force is used to change their shape.