When you toss a toy into the air, gravity pulls it back down. A parachute slows that fall by trapping air underneath and creating a pushing-back force called air resistance. You cut a large circle from a plastic bag, poke six holes around the edge, and tie six equal strings to the holes. Attach a small toy to the loose ends and drop the whole thing from a high spot. The plastic fills with air and the toy floats down gently. Gravity still wins, but air resistance slows the descent.

Heavier objects hit harder when they fall, and this experiment shows why. You drop objects of different weights onto a flat empty can and compare the dents each one leaves. A heavier object makes a bigger dent because gravity pulls it down with more force. The stored energy — called potential energy — depends on both weight and height, and the dent records how much was released on impact.

Gravity pulls every object down, regardless of how heavy or light it is. That might seem obvious, but in normal air the feather drifts while the coin drops fast — air resistance clouds the picture. To remove that variable, you place a coin and a feather inside a clear plastic tube sealed with rubber stoppers and pump the air out with a vacuum pump. Flip the tube in normal air first: the coin wins easily. Pump the air out and flip again. With no air resistance, the feather falls almost as fast as the coin. Let the air back in and the difference returns immediately.