Grade Level/Subject Unit Enduring Understanding SOL Objectives 8th Grade Waves Energy can travel in various forms. Waves are one form. There are several types of waves, each with similar characteristics. Title Lesson Objective Inquiry Level Materials Needed How is it Level 2/3? Waves Lab Identify and model sinusoidal and compression waves. 2 Plastic slinky for each group of students The question and the methods are defined in terms of how to create examples of the waves. The ‘solution’ or analysis of the waves is up to each student. The student will investigate and understand characteristics of sound and technological applications of sound waves. Key concepts include a) wavelength, frequency, speed, and amplitude; b) resonance; c) the nature of mechanical waves; and d) technological applications of sound. Name__________ Date___________ Waves Lab The purpose of this lab is for you to observe different types of waves, and to observe changes that can be made to the same types of waves i.e., frequency, wavelength, and velocity. 1. Take the slinky and sit on the floor with your partner. 2. Stretch the slinky out so that it is tight (not too tight). 3. Holding the slinky on the ground, shake one end of it from side to side. 4. Make a diagram in Box 1 of the wave as it would look if you took a picture of it. Box I 5. Shake the slinky in the same way only shake it harder (moving your hand farther with each shake than before to create a larger wave.) 6. Make a diagram in Box II of the wave as it would look if you took a picture of it. Box II 7. Shake the slinky the same way you did the first time, only now shake it faster. 8. Make a diagram in Box III of the wave as it would look if you took a picture of it. Use the box below. Box III 9. With the slinky stretched out in front of you, instead of shaking it from side to side, abruptly push and then pull the end of the slinky. 10. Make a diagram of the wave as it would look if you took a picture of it. Use the box below. Questions - Part I: 1. According to the law of conservation of energy, energy cannot be created or destroyed. If so, what is the source of energy that created the wave in this lab? 2. Once the energy enters the slinky at your hand, where does it go? 3. Describe the motion of the material of the slinky as the wave passes through it. 4. What moves down the slinky as the wave propagates (propagates means ‘moves forward’)? Part II: Refer to Ch 11 pg. 326 in your book if needed. 5. What is sound pitch directly related to? 6. What is the medium through which sound usually travels? 7. What things can affect the rate at which sound travels? 8. Can sound travel through space? 9. Can light travel through space? 10. What type of wave does sound travel in? General Questions 11. Which generally plays a higher pitch, a violin or a string bass? What is the difference in the waves created by these two instruments? 12. What is the frequency range of the normal human ear? 13. What are sounds below 20 Hz called? 14. What are sounds above 20000 Hz called? 15. What trait of the wave - amplitude, frequency, or wavelength is responsible for how loud sounds are? 16. What unit is loudness measured in?