2Energy is sometimes transferred from place to place by traveling in waves. Sound and light travel in waves. Some substances transport energy through them in waves – like water waves.
3A wave is an energy disturbance that moves in a consistent manner A wave is an energy disturbance that moves in a consistent manner. Some waves can travel through a vacuum (no matter), while others travel through matter (called a medium). Waves that pass through a medium do so without causing permanent movement of the medium.
4There are different types of waves with different types of movement.
5Ocean waves travel in transverse waves Ocean waves travel in transverse waves. A transverse wave causes particles to move up and down while the wave moves forward (perpendicular to the wave motion).
9Longitudinal waves (also called compression waves) move particles back and forth parallel to the wave motion. Sound and earthquake waves are longitudinal waves.
10Waves have properties and scientists use these properties to describe specific waves.
11Transverse waves have crests and troughs, a crest being the highest point of displacement, and the trough the lowest point of displacement. A node is the point where it crosses the median line.
12The wavelength of a transverse wave is defined as the distance from one crest (or top) of a wave to the next crest on the same side.
13The wavelength of a longitudinal wave is measured from the center of one compression to the center of the next.
14The frequency of a wave is the number of wavelengths that pass a point in a second. (You could count the frequency of ocean waves by standing in one place on a dock and counting how many wave crests pass in a given time period.) Frequency is usually measured in Hertz or cycles per second.
15The wavelength and frequency of the same wave are related The wavelength and frequency of the same wave are related. As frequency increases wavelength decreases and as frequency decreases wavelength increases. (Or you can say it the other way As wavelength increases, frequency decreases, etc.).
16The amplitude of a wave is measure of the amount of displacement it causes. In other words, the amplitude is the distance from the center of the wave to it’s highest point.
17Waves also interact with each other in various ways.
18Wave interference can occur between waves Wave interference can occur between waves. Interference can increase wave amplitude if the crests and troughs of the waves coincide. If the crest and trough of two waves coincide, they can cancel each other or reduce the amplitude.
19Waves can also be reflected when they hit a surface.
21Sound travels in longitudinal waves Sound travels in longitudinal waves. Sound waves are made when an object vibrates and causes surrounding air molecules to take on a compression wave motion. This motion is picked up by our eardrums and translated in our brains into sounds.
22Sound waves can only travel in a medium (where there is matter) Sound waves can only travel in a medium (where there is matter). They can not travel in a vacuum.
23Changes in wavelength of sound waves cause volume changes, while changes in frequency result in pitch changes.
24Sound waves travel at a speed of 330 m/s in air at zero degrees Celsius. Sound travels at different speeds in different media (water, wood, etc.) and at different temperatures.
35Light waves can also be refracted (bent). When our eye looks at the pencil in water, it looks broken because the light waves have been bent by the differing substances (air is less dense than water).
36The velocity of light waves is consistent at Speed of LightThe velocity of light waves is consistent at299,792,458 m /s.
37Waves are constantly surrounding us with light, sound, and lots of other types of energy!
38Words to Rememberamplitude trough crest wavelength frequency pitch electromagnetic spectrum transverse wave longitudinal wave
39Which numbered term above goes with A (Answer with a number 1-5.) 1. crest2. trough3. wavelength4. node5. amplitudeWhich numbered term above goes with Aon the picture?(Answer with a number 1-5.)
40Which numbered term above goes with B (Answer with a number 1-5.) 1. crest2. trough3. wavelength4. node5. amplitudeWhich numbered term above goes with Bon the picture?(Answer with a number 1-5.)
41Which numbered term above goes with C (Answer with a number 1-5.) 1. crest2. trough3. wavelength4. node5. amplitudeWhich numbered term above goes with Con the picture?(Answer with a number 1-5.)
42Which numbered term above goes with D (Answer with a number 1-5.) 1. crest2. trough3. wavelength4. node5. amplitudeWhich numbered term above goes with Don the picture?(Answer with a number 1-5.)
43Which numbered term above goes with E (Answer with a number 1-5.) 1. crest2. trough3. wavelength4. node5. amplitudeWhich numbered term above goes with Eon the picture?(Answer with a number 1-5.)
44What is a wave?A: traveling energy that causes a temporary disturbanceB: permanent movement of a mediumC: energy that can only travel in a vacuumD: energy that can only travel through matter
45Which of the following is NOT true? Sound waves A: are compression waves.B: are longitudinal waves.C: must travel through a medium.D: are transverse waves.
46Transverse waves A: have a series of compressions and rarefactions. B: move particles perpendicular to direction of the wave.C: have no amplitude.D: must always travel through a medium.
47A: they are the only type of transverse waves. Electromagnetic waves are unique becauseA: they are the only type of transverse waves.B: they are the only type of compression waves.C: they can travel in a vacuum.D: they require a medium in which to travel.
48Which is true of light waves? A: they are transverse waves.B: they are electromagnetic waves.C: they can not travel in a vacuum.D: A & C only
49A: particles move back in forth in motion parallel to the wave motion. In longitudinal wavesA: particles move back in forth in motion parallel to the wave motion.B: particles move up and down in motion perpendicular to the wave motion.C: the particles in the medium are permanently displaced when a wave passes through.D: there is no temporary displacement of particles as the wave moves through.
50The frequency of a wave is A: measure of the height of a wave.B: the same as the wavelength.C: the same as wave velocity.D: the number of wavelengths that pass a point in a given period of time.
51As the wavelength of a wave increases A: the frequency remains the same.B: the velocity increases.C: the frequency decreases.D: the frequency increases.
52Some wavelengths of light are not visible to the human eye. A: TrueB: False
53Red light has a shorter wavelength than violet light. A: TrueB: False
54Yellow light, X-rays, microwaves, and radio waves are all parts of the electromagnetic spectrum. A: TrueB: False
55B: the entire electromagnetic spectrum Red, orange, yellow, green, blue, and violet light wavelengths combine to formA: black lightB: the entire electromagnetic spectrumC: white lightD: infrared light
56Sound waves are affected by temperature and density of the medium they travel in. A: TrueB: False
57Different colors of light have different A: crestsB: amplitudesC: wavelengthsD: speeds
58Changing the frequency of a sound wave changes the A: volumeB: amplitudeC: pitchD: tone