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Nature & Properties of Sound Waves. Video Link: . Think Pair Share. Discuss with your partner what you saw in the video. Draw a conclusion for how you think the flame was able to be extinguished, or put out, with only a human voice. Nature of Sound Waves.
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Nature & Properties of Sound Waves Video Link:
Think Pair Share • Discuss with your partner what you saw in the video. • Draw a conclusion for how you think the flame was able to be extinguished, or put out, with only a human voice.
Nature of Sound Waves • When an object, like a radio speaker or guitar string vibrates, it collides with nearby particles in the air, transferring some of the energy to them. • The process of collisions & energy transfer forms a sound wave.
Nature of Sound Waves • What type of mechanical wave are sound waves? • Longitudinal/compressional waves~ compress and expand as they travel.(Think of the movement of a slinky toy as it transfers energy.)
Nature of Sound Waves • Sound waves are mechanical waves~ they require a medium through which to travel. • What do footsteps sound like on the moon?
Nature of Sound Waves • On the moon, there is no atmosphere and therefore no particles for energy to transfer. No matter = no sound waves. How can astronauts communicate in space?
Behaviorof Sound Waves • Behavior of sound waves: Sound waves can be reflected~ sonar uses reflected sound waves to detect objects underwater.
Nature of Sound Waves • Can sound waves travel through solids, liquids, and gases? • Yes, solids, liquids, and gases carry sound waves.
Speedof Sound Waves • With the knowledge that sound waves need particles in order to transfer energy, Think Pair Share with your partner to answer the following question: • In what material~ solid, liquid, or gas, do sound waves travel the fastest? The slowest?
Speedof Sound Waves • Which material allows sound waves to travel faster? • TRY THIS: knock gently on the top of your desk. • Now, press your ear against the top of your desk and knock gently.
Speedof Sound Waves • What did you notice or observe about the sounds you heard? • What inference can you make about why this occurred?
Speedof Sound Waves • When particles are closer together, such as in liquids and especially solids, energy is transmitted quicker. Therefore, the speed of sound waves depends on the material it is passing through. • Bucket Brigade!
Speedof Sound Waves • Speed does NOT depend on loudness~loud and soft sound waves travel at the same speed.
Think Pair Share • Discuss with your partner the Essential Question: What causes sound waves and how do they travel? • Write a one-sentence statement to answer this question and post it on my office door when you are dismissed.