10 Fun Physics Experiments

The center of gravity of any object is the point where you can balance it as if all the masses were gathered there. In this demonstration, the center of gravity is directlybelowthe spot where the toothpick rests on the rim of the glass. It seems like it is not using the glass to balance at all.

Supersaturation happens when a solution holds more dissolved material than the solvent allows under normal conditions. This means it cannot dissolve any more. Carbonation in a drink is a supersaturated solution of carbon dioxide gas. A Diet Coke and Mentos eruption shows an extreme example of reaching the point where the substance can dissolve no more.

This experiment shows air pressure's power. Before boiling, the can held air and water. Boiling changes the water to water vapor, a gas. This vapor pushes the air out of the can into the air. Turning the can upside down in the water lets the water vapor condense back to liquid water. Liquid water molecules pack tighter than gas molecules, so most of the water vapor turned into just a few drops, taking up much less space.

Carbon dioxide has one carbon atom and two oxygen atoms, weighing 44 grams per mole (a certain number of molecules). Oxygen weighs 32. Thus, carbon dioxide is heavier than oxygen.

Usually, when you shake a plate, diaphragm, or membrane, the areas where it moves show up in a thin layer of particles, paste, or liquid. Different patterns appear in the chosen medium based on the plate's shape and the shaking speed. Different tones make different patterns.

Lenz's Law explains this. An electromagnetic field hitting a conductor makes an electrical current. This current then makes a counter-magnetic field that fights the original magnetic field creating the current. If one magnetic field makes another electric current, the currents go opposite ways. If these currents are in two loops, they must rotate in opposite directions. The opposing currents push each other away.

A battery generates directed electricity. This device uses electrochemical cells to change stored chemical energy into electrical energy. Each cell has a positive terminal, the cathode, and a negative terminal, the anode. Electrolytes let ions move between the electrodes and terminals. This movement lets current flow from the battery to do work. The Lemon Battery is an old classroom experiment showing how a battery changes stored energy.

Levitation is real. Hovercars are coming. What is the science? In a weak applied field, a superconductor expels almost all magnetic flux.

Heinrich Rubens, a German physicist, invented the Rubens' tube in 1905. This tube, also called a flame tube, shows the link between sound waves and sound pressure.

The Lorentz Force acts on a point charge moving along a wire in a magnetic field. The force forms a right angle with both the current and the magnetic field. This force lets you suspend a current-carrying object between two magnets.