There are still more simple science experiment that you can do. Finding the Speed of Light with Marshmallows A Take-Home Lab is another simple experiment which you can try even at home. I have heard that at 16 years old, Albert Einstein constantly wondered what it would be like to ride on a beam of light. Albert Einstein born March 14, 1879 and died April 18, 1955, was a German-born theoretical physicist who is widely considered to have been one of the greatest physicists of all time. While best known for the theory of relativity and specifically mass-energy equivalence, E=mc², he was awarded the 1921 Nobel Prize in Physics “for his services to Theoretical Physics, and especially for his discovery of the law of the photoelectric effect.”Einstein’s many contributions to physics include his special theory of relativity, which reconciled mechanics with electromagnetism, and his general theory of relativity which extended the principle of relativity to nonuniform motion, creating a new theory of gravitation.

His other contributions include relativistic cosmology, capillary action, critical opalescence, classical problems of statistical mechanics and their application to quantum theory, an explanation of the Brownian movement of molecules, atomic transition probabilities, the quantum theory of a monatomic gas, thermal properties of light with low radiation density which laid the foundation for the photon theory, a theory of radiation including stimulated emission, the conception of a unified field theory, and the geometrization of physics. Students in physics always seem to be fascinated by the properties of light. However, speed-of-light demonstrations often require extensive preparation or expensive equipment. I have prepared a simple classroom demonstration that the students can also use as a take-home lab. The activity requires a microwave oven, a microwave-safe casserole dish, a bag of marshmallows, and a ruler. The oven must be of the type that has no mechanical motion-no turntable or rotating mirror.

If there is a turn-table, remove it first. First, open the marshmallows and place them in the casserole dish, completely covering it with a layer one marshmallow thick. Next, put the dish of marshmallows in the microwave and cook on low heat. Microwaves do not cook evenly and the marshmallows will begin to melt at the hottest spots in the microwave. Heat the marshmallows until they begin to melt in four or five different spots. Remove the dish from the microwave and observe the melted spots. Take the ruler and measure the distance between the melted spots. You will find that one distance repeats over and over. This distance will correspond to half the wavelength of the microwave, about 6 cm. Now turn the oven around and look for a small sign that gives you the frequency of the microwave. Most commercial microwaves operate at 2450 MHz. All you do now is multiply the frequency by the wavelength. The product is the speed of light! Example of the computation with the given and constant formula. Velocity = Frequency ‘ Wavelength Velocity = 2450 MHz ‘ 0.122 m Velocity = 2.99 ‘ 108 m/s This works in your physics class, often with less than 5% error. Then the students can eat the marshmallows.