Exploring Light With Holographic Chocolate
Students explore how light interacts with matter. Using the principles of spectroscopy, they learn how light can cause molecules to react by entering into an excited state. This activity addresses diffraction grating, which is in a spectrometer (a specialized instrument used to track and measure the path of different wavelengths of light). This instrument is used in many applications that study light-matter interactions. Students apply a diffraction grating to chocolate, allowing them to observe the ray of light being separated into different colors and wavelengths and how light can interact differently with common materials by altering their properties. Students further explore light by designing light-powered products and presenting their designs to the class.
A student’s product, a laser maze, uses mirrors to refract light to make it get to a certain point at the end of the maze.Copyright Hollis McKinney
Engineers use the information from spectroscopy to design and explore different systems that use light-matter interactions. For example, companies that make solar panels need to know the power conversion efficiency, which describes the efficiency of electricity produced from light absorbed. One contribution to this efficiency is the range of colors absorbed.
After this activity, students should be able to:
- Explain that light travels in a straight line until it strikes an object and is reflected or travels through one medium to another and is refracted.
- Describe light as a spectrum that includes visible and invisible light.
- Summarize the uses of energy, including mechanical, light, thermal, electrical, and sound energy.
- Apply the use of electromagnetic waves in applications by creating a final product that harnesses light energy.
- Explain the differences and similarities between diffraction and refraction.