The Phenomemon of Sound Waves
A lesson plan including various lab stations to address these topics: Students will understand that sound is a form of energy that travels in waves referred to as compressional waves; understand that sound waves can travel through different mediums, including solids, liquids, and gases; understand and observe that sound waves travel in a given direction until an outside force or object gets in the way of its motion and reflects it; and observe a variety of sound waves . They will record their observations in a wave booklet. This lesson includes differentiation, extension and assessment activities.
- Understand that sound is a form of energy that travels in waves referred to as compressional waves
- Understand that sound waves can travel through different mediums, including solids, liquids, and gases
- Understand and observe that sound waves travel in a given direction until an outside force or object gets in the way of its motion and reflects it
- Observe a variety of sound waves in lab stations and record their observations in a wave booklet
- Hypothesize what happens to sound waves when they reach a wall or other solid, flat object.
- If sound can't travel in space, hypothesize what other modes of communication astronauts can use when they are outside the space shuttle?
- Explain why, based on the behavior of sound waves, a classroom with a tile floor is louder than a library that is carpeted.
- How does sound travel when you have a conversation with your friends?
- Think about what it is like to hear things under water. Debate whether sound travels better in liquids (like water), gases (air), or solids (like putting your head down on a desk and having someone slam a book down on the surface)?
- Discuss why you see lightning before you hear thunder during storms.
- Students can still perform each of the lab activities, but have them compare what they learn about sound waves to what they have learned about light waves. Have students in groups create concept maps comparing the two types of waves. Groups can present diagrams to the class and demonstrate their understanding of the two types of waves by showing the class how to "read" their map. Maps should be colorful and creative and contain the following concepts and information about each type of wave in an organized format:
- Transverse waves carry light energy, do not require a medium through which to travel, and can travel through space or in a vacuum. Transverse waves on Earth can move through any medium. When transverse waves do travel through a medium, that medium will move at right angles to the direction the wave is traveling. Transverse waves carry different types of light energy, found in the electromagnetic spectrum, and they travel faster than the speed of sound.
- Students should also include a labeled diagram of a transverse wave showing a crest, a trough, amplitude, rest position, and wavelength.
- Compressional waves carry sound energy and require a medium through which to travel. Matter vibrates in the same direction as the wave is traveling, and waves travel slower than light or transverse waves.
- Students should also include a labeled diagram of a compressional wave that shows compression, rarefraction, and wavelength.
For this lesson, you will need:
- A few paper clips
- Tuning fork
- Basin of water
- Rubber band strung between two pegs or nails
- Metal fork and spoon
- Steel yardstick or ruler
- Musical instruments or a musical tape, record, or CD
- A slinky
- A set of glasses and a spoon for each group of students
- Six copies of theSound Waves Seen activity sheetfor each student.