A Wave Terminology
1. The ______of a wave is determined by the rate at which the source produces the wave.
2. Waves that require a medium are ______waves.
3. The ______of a wave is determined by the amount of energy that the wave carries.
4. The particles vibrate parallel to the direction of energy transmission in ______waves.
5. The time required for one complete cycle is called the ______.
6. The particles vibrate perpendicular to the direction of energy transmission in ______waves.
7. The ______of a wave is determined by the material through which it travels.
8. Sound waves are an example of ______and ______waves.
9. Use the diagram below to identify amplitude and wavelength.
10. The ______is a group of transverse waves that can travel through a vacuum.
1. frequency / 2. mechanical / 3. amplitude / 4. longitudinal / 5. period6. transverse / 7. speed / 8. longitudinal; mechanical / 9. amplitude (D) wavelength (A) / 10. Elcectro-
magnetic Spectrum
B Wave Motion
1. A fisherman notices that wave crests pass the bow of his boat every 3.0 s. He measures the distance between two consecutive crests to be 7.5 meters. How fast are the waves traveling?
2. A particular sound wave in air has a frequency of 262 hertz and travels at 330 m/s. How far apart are the compressions of this sound wave?
3. Calculate the wavelength of a radio wave that has a frequency of 108 MHz. (Note: All electromagnetic waves travel at the speed of light)
4. A sonar signal (sound wave) is sent from a ship at the water’s surface to ocean floor below. The speed of sound in water is 1400 m/s. The reflected signal is detected 3.00 s later. How deep is the ocean beneath the ship?
5. What is the wavelength of a 10 MHz ultrasonic sound wave traveling through air on a day when the temperature is 20oC and the speed of sound is 343 m/s?
6. An open-ended organ pipe is 3.5 m long. If the speed of sound is 343 m/s, what is its fundamental frequency?
7. A string 1.5 m long with a mass of 2.1 g is stretched between two fixed points with a tension of 95 N. Find the frequency of the fundamental on this string.
8. A guitar string 62 cm long vibrates with a standing wave that has three antinodes. (a) Which harmonic is this?
(b) What is the wavelength of this wave?
9. The organ pipe in the figure below is 2.5 m long. Speed of the sound wave is 343 m/s.
(a) What is the frequency of the standing wave shown in the pipe?
(b) What is the fundamental frequency of this pipe?
10. A pair of in-phase stereo speakers is placed side-by-side, 0.60 m apart. You stand directly in front of one of the speakers, 1.0 m from the speaker. What is the lowest frequency that will produce constructive interference at your location? (Speed of sound is 343 m/s.)
11. Two wave pulses on a string approach one another at the time as shown in the figure below. Each pulse moves with a speed of 1.0 m/s. Make a careful sketch of the resultant wave at the times 2.0 s, 2.5 s, 3.0 s, and 4.0 s, assuming that the superposition principle holds for these waves.
12. Two wave pulses on a string approach one another at the time as shown in the figure below. Each pulse moves with a speed of 1.0 m/s. Make a careful sketch of the resultant wave at the times 2.0 s, 2.5 s, 3.0 s, and 4.0 s, assuming that the superposition principle holds for these waves.
1. 2.5 m/s / 2. 1.26 m / 3. 2.78 m4. 2100m / 5. 3.43 x 10-5 m / 6. 49 Hz
7. 87 Hz / 8. a. 3
b. 41 cm / 9. a.100 Hz
b. 34 Hz
10. 2.1 kHz / 11. see diagram below / 12. see diagram below
11 12
C Waves in Mediums and at Boundaries
1. What are the factors that will influence the speed of a wave in a rope, string, or wire?
2. Consider a rope fixed at one end. Describe the characteristics of the reflected wave listed below.
a. Orientation:
b. Amplitude:
c. Speed:
d. Wavelength:
3. Consider a rope free at both ends. Describe the characteristics of the reflected wave listed below.
a. Orientation:
b. Amplitude:
c. Speed:
d. Wavelength:
4. A wave is traveling along a string when it encounters a new string (medium) that is thinner and less dense.
a. Describe the characteristics of the reflected wave listed below.
i. Orientation:
ii. Amplitude:
iii. Speed:
iv. Wavelength:
b. Describe the characteristics of the transmitted wave listed below.
i. Orientation:
ii. Amplitude:
iii. Speed:
iv. Wavelength:
5. A wave is traveling along a string when it encounters a new string (medium) that is thicker and more dense.
a. Describe the characteristics of the reflected wave listed below.
i. Orientation:
ii. Amplitude:
iii. Speed:
iv. Wavelength:
b. Describe the characteristics of the transmitted wave listed below.
i. Orientation:
ii. Amplitude:
iii. Speed:
iv. Wavelength:
D Wave Interactions
1. Label the diagram shown below with the appropriate letters.
a) Normal
b) Angle of incidence
c) Angle of reflection
d) Incident ray
e) reflected ray
2. Light traveling through air is incident upon a piece of crown glass at an angle of 45o.What is the angle of refraction to the nearest degree?
3. A ray of light passes from air into water at angle of 30o. What is the angle of refraction?
4. A light wave travels through air into an unknown liquid. If the angle of incidence is 30o and the angle of refraction is 22o,
a. what is the index of refraction for the liquid?
b. what is the liquid?
5. Use figure 1 on the next page to find θ1 and θ2.
6. Use figure 2 on the next page to answer this question. A 2 m vertical pole extends from the bottom of a swimming pool to a point 50 cm above the water surface. Sunlight hits the water at an angle of 55o measured from the surface of the water. What is the length of the shadow of the pole on the bottom of the pool?
7. Calculate the speed of light in the following:
a. Quartz
b. Polyethylene
c. Diamond
8. What is the critical angle for a sample of flint glass surrounded by air?
9. Light falling on two slits 0.042 mm apart produces a 5th order maximum at 7.8o. What is the wavelength of the light?
10. At what angle will 650 nm light produce a 2nd order maximum when falling on a grating whose slits are 1.15 x 10-5 m apart?
11. White light passes through two slits 0.50 mm apart and an interference pattern is observed on a screen 2.5 m away. A 1st order red maximum is observed 3.5 mm away from the central maximum and a 1st order violet maximum is observed 2.0 mm from the central maximum. Calculate the wavelength of red and violet light.
blocked sunrays
FIGURE 1 FIGURE 2
incident wave reflected wave 55o water surface
38o θ1
n = 1.58
n = 1.22
θ2
refracted wave
1. See instructor / 2. 28o / 3. 22o / 4. a) 1.33 b) water5. θ1: 38o θ2: 52.9O / 6. 1.07 m / 7. a) 2.05x108 m/s b) 1.97x108m/s c) 1.23x108m/s / 8. 38.4o
9. 1.1x10-6m / 10. 6.49o / 11. red 7x10-7m / violet 4x10-7m