Physics 011

A of PQ#11A

Chapter 11 : Vibrations and Waves
Practice Questions

1.	The unit for the spring constant is The correct answer: N/m Review Section 11-1 in Giancoli.
2.	The unit for the period is Your answer: s
3.	The unit for frequency is The correct answer: Hz Review Section 11-1 in Giancoli.
4.	The unit for wavelength is The correct answer: m Review Section 11-7 in Giancoli.
5.	The unit for the product of wavelength and frequency is The correct answer: m/s Review Section 11-7 in Giancoli.
6.	The amplitude of the wave in the figure is The correct answer: 4 m Review Figure 11-23 in Giancoli.
7.	The wavelength is The correct answer: Cannot be determined from the given information. The figure only shows the temporal (time) behavior of the wave. Review Section 11-7 in Giancoli.
8.	The frequency of the wave is Your answer: .5 Hz
9.	A stretched spring, fixed at both ends, vibrates at a frequency of 12 Hz with a standing transverse wave pattern as shown. What is this spring's fundamental frequency? The correct answer: 4 Hz. You should have divided by 3. Review Section 11-11 in Giancoli.
10.	A stretched spring, fixed at both ends, vibrates at a frequency of 12 Hz with a standing transverse wave pattern as shown. What would be the frequency of the first overtone? Your answer: 8 Hz
11.	A stretched spring, fixed at both ends, vibrates at a frequency of 12 Hz with a standing transverse wave pattern as shown. If the string is 5 meters long, what is the wave velocity? The correct answer: 40 m/s Review Section 11-11 in Giancoli.
12.	If a string has a wave speed of 200 m/s and a mass per length ratio of 1.2 g/m, what is the tension? The correct answer: 48 N Convert grams to kilograms. Review Section 11-11 in Giancoli.
13.	A stretched cord has a fundamental frequency of 144 Hz, a length of .9 m, and a mass of 2 g. What is its wave speed? Your answer: 259 m/s
14.	A stretched cord has a fundamental frequency of 144 Hz, a length of .9 m, and a mass of 2 g. What is the tension on the cord? The correct answer: 149 N Review Example 11-13 in Giancoli.
15.	The animation shows the Tacoma Narrows Bridge (see Online Destinations) shortly before its collapse. What is its frequency? The correct answer: .50 Hz Measure the time for the car to make one complete vibration. Review Section 11-12 in Giancoli.
16.	The animation shows the Tacoma Narrows Bridge (see Online Destinations) shortly before its collapse. The distance between the bridge towers (nodes) was about 860 meters and there was also a midway node. What was the wavelength of the standing torsional wave? The correct answer: 860 m Review Section 11-12 in Giancoli.
17.	The animation shows the Tacoma Narrows Bridge (see Online Destinations) shortly before its collapse. What is the amplitude? The correct answer: 4 m Compare it to the size of the car. Review Section 11-12 in Giancoli.
18.	The picture shows two moving triangular waves.The scale shown at the bottom holds for the vertical scale, also. What is the wavelength of the black wave? The correct answer: 4 cm Measure the wavelength from peak to peak. Review Section 11-7 in Giancoli.
19.	The picture shows two moving triangular waves.The scale shown at the bottom holds for the vertical scale, also. What is the frequency of the black wave? The correct answer: .25 Hz Pick a place and count the seconds for the wave to return to the same location. Review Section 11-7 in Giancoli.
20.	The picture shows two moving triangular waves.The scale shown at the bottom holds for the vertical scale, also. What is the frequency of the red wave? The correct answer: .33 Hz Pick a place and count the seconds for the wave to return to the same location. Review Section 11-7 in Giancoli.
21.	The picture shows two moving triangular waves.The scale shown at the bottom holds for the vertical scale, also. What is the velocity of the black wave? The correct answer: 1 cm/s Velocity is the product of wavelength and frequency. Review Section 11-7 in Giancoli.
22.	The picture shows two moving triangular waves.The scale shown at the bottom holds for the vertical scale, also. What is the velocity of the red wave? The correct answer: 2 cm/s Velocity is the product of wavelength and frequency. Review Section 11-7 in Giancoli.
23.	The picture shows two moving triangular waves.The scale shown at the bottom holds for the vertical scale, also. What is the amplitude of the red wave? The correct answer: 2 cm Review Section 11-7 in Giancoli.
24.	If the effective spring constant of a 2000 kg older car (with poor shocks) is 60000 N/m, what is the period of its vibration after hitting a bump? The correct answer: 1.15 s Review Section 11-3 Giancoli.
25.	What is the effective spring constant of a 10 kg, 1.5 m simple pendulum? The correct answer: 65 N/m Review Section 11-4 Giancoli.