Physics experiments expose the nature of light, matter and the world around you. Although some experiments can't easily be performed by the average person, projects such as extracting the relationship between a lens' magnification and the distance from the object are performed using basic materials. With a laser pointer and soda pop, you can figure out how much sugar is in the beverage without tasting it.
The magnification experiment requires a rudimentary understanding of optics, lenses and the attendant equations. The distance between the object you're viewing and the degree of magnification of the lens gives you the optical distance equation.
The principle of refraction plays a part in the laser and sugary soda experiment. Using Snell's law from any physics text on optics, you can find the angle of refraction between the water's surface and the air above it by placing an object extending into both mediums and seeing how much it bends. A laser beam is a coherent source of light with a single wavelength, which allows you to measure the difference between the angle of refraction of soda and water with respect to the air. The only reason soda differs from water is because of the sugar content, so this is tantamount to a measurement of the sugar content in soda.