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.
A catapult can be used to make a ball follow different trajectories. In the top picture, the ball follows a high trajectory to go over the castle wall. In the bottom picture, it follows a low trajectory to go into the castle wall. Both of these are bad news for the people inside the castle!