Starter On the back of the ScienceWorld magazine on your desks read about Scare Science. On your paper, complete the Analyze It. 1
Waves can transfer ________ over __________ without moving matter the _________ distance. Waves that ________ energy through matter are known as _____________ waves. A way to classify waves is how they move; ______________, ______________ and ______________. In a _______________ wave, the ________ in which the wave travels is ______________, or at a right angle, to the direction of the disturbance. In a _______________ wave, the wave travels in the same direction as the disturbance. energy distance entire transfer mechanical up-and-down side-to-side forward-to-backward transverse direction perpendicular longitudinal 2
Two waves can _________ energy to or take away energy from each other. When _________ increases more wave crests pass a fixed point each second. That means that wavelength ________. So, as frequency increases, wavelength ________, and the opposite is true. Two waves can _________ energy to or take away energy from each other. The adding of two waves is called _____________ _____________. It builds up, or constructs, a larger wave out of two smaller ones. The ____________ of two waves is called ____________ _____________. Sound is a type of ______________ wave. frequency shortens increases add constructive interference subtracting interference destructive mechanical 3
Sound travels __________ through liquids than it does through gases. instrument You have a sound-making _______________ within your own body. It is a set of _____ _____ within the _____ _____, or __________, in your throat. Your vocal cords __________ when you breathe to allow air to pass in and out of your __________. Your vocal cords _____ up and draw close together when you are about to speak or sing. Sound waves are _______________ by first causing the __________ to _________, then the vibrations travel through the __________, _____, and __________ to the inner ear, and lastly cells in the __________ detect the vibrations and send a message to the brain. Sound travels _____ __________ than light, and it does not always travel at the same speed. Two main factors affect the speed of sound: the __________ that makes up the _________ and the _______________. Sound travels __________ through liquids than it does through gases. Sound also travels __________ through a medium at __________ temperatures than at __________ ones. vocal cords voice box larynx relax windpipe tense detected eardrum vibrate hammer anvil stirrup cochlea more slowly material medium temperature faster faster higher lower 4
The __________ of a sound wave determines the __________ of the sound you hear. A _______________ wave makes a _______________ sound. A _____________ wave makes a _____________ sound. Most people with good hearing can hear sounds in the range of _______________ hertz. Sounds below __________ hertz are called _______________ and sounds above _________ are called _______________. All objects have a __________ at which they __________ called a __________ frequency. When a sound wave with a particular frequency ___________ an object that has the same natural frequency, __________ __________ occurs. frequency pitch high-frequency high-pitched low-frequency low-pitched 20-20,000 20 infrasound 20,000 ultrasound frequency vibrate natural encounters constructive interference 5
__________ is the measure of wave _________. Each _________ __________ and each _________ __________ has its own particular sound _________, or _________. The _________ _________ is the change in ___________ pitch that occurs when the sound or the __________ of a sound is moving As a sound moves __________ you the frequency and therefore the pitch _________. As the sound moves ________ the sound waves still move ________ but are _________ ________ so the frequency ________ and you hear a _________ pitch. __________ is the measure of wave _________. The _________ the amplitude, the more _________ a sound wave has and the ________ the sound will be. instrument musical human voice quality timbre Effect Doppler perceived receiver toward increases away toward you further away decreases lower Amplitude energy greater intensity louder 6
_________ waves are used to detect objects . Over ________ and _________, a sound gets ________ and _________ until the sound becomes __________. the pitch, however, does not typically change as the _______ grows ________. Sometimes it is _________ to change sound _________ without changing the pitch and quality of the sound. We can do this by ________ energy to or _________ energy _________ from a sound wave. _________ can also refer to the way sound waves __________ inside a space. Hair cells inside your ears are extremely __________. __________ exposure to _____ decibels or louder can cause damage or _________ the cells. _________ waves are used to detect objects . time distance weaker weaker undetectable sound weaker intesity desirable adding taking away Acoustics behave sensitive Continual 90 destroy Ultrasound 7
Sonar stands for _____ ________ __ _____. Sonar can be used for finding enemy __________, schools of ______, map the ______ floor, find ______ ships, to break up ______ stones, to ______ ________ organs, and look at babies during __________. Music is sound with clear _________ or __________. Musical instruments produce __________ and __________ when made to _________ at their natural frequencies. sound navigation and ranging submarines fish ocean sunken examine kidney internal pregnancy pitches rhythms pitches rhythms vibrate 8
The three main types of musical instruments are _________, _____, and _________. For __________ instruments the vibration of the _______ causes the sound. For the _____ instruments sound is produced by blowing into a _________ and vibrating a column of air. For ________ instruments someone hits the _____ skin which causes vibrations and sends out sounds waves. A _________ must do two things: 1) __________ the sound that is spoken into it and 2) it must _________ the sound that arrives as a signal from somewhere else stringed wind percussion stringed strings wind mouthpiece percussion tight telephone record reproduce 9
Starter Suppose you are riding in a car down the street and pass a building where a fire alarm is sounding. Will the sound you hear change as you move up to, alongside, and past the building? Why or why not? 10
On pps. C67-C68 do questions1-4, 11-17, and on p. C69 do questions 1-4
Study for Vocabulary Test 12
Vocabulary Test Once you finish your test please open the ScienceWorld magazine to pps. 20-22 and read and bats. The back of your test has some questions about your reading. 13
Study for test 14
Test over Waves Ch. 1 & 2 15