Homework

Physics 101 - Homework 1

Instructions: Complete this form and click submit. The answers will be posted on the course home page after the due date and before the next exam. If you want to change any of your answers after you click submit, then go back and give your answers again and click submit. Recall that the homework is not part of your grade. However, everyone is expected to complete all homework sets. A few of these questions may appear on an exam or clicker quiz.

Your Name: e.g. John Doe

Your Campus ID: e.g. 12345678

Your SFA Email Address: e.g. doejd@titan.sfasu.edu

Due Date 9/11/2007 11:00PM

1. Which of the following is not a medium which will transmit sound?

a. solids

b. liquids

c. gasses

d. vacuum

2. Two waves having the same amplitude and frequency interfere as a crest meets a trough. The result will be _____.

a. constructive interference

b. destructive interference

c. resonance

d. standing waves

3. What is the frequency of a simple pendulum if its period is 20 seconds?

a. 0.1 Hz

b. 50 Hz

c. 0.05 Hz

d. you can't get frequency from period

4. The vibrations of a longitudinal wave move in a direction
a. along the direction of the wave travel

b. at right angles to the direction of wave travel

5. A node is a position of
a. minimum amplitude

b. maximum amplitude

c. medium amplitude

6. A floating leaf oscillates up and down two complete cycles in one second as a water wave passes by. The wave’s wavelength is 10 meters. What is the wave’s speed?
a. 2 m/s

b. 10 m/s

c. 20 m/s

d. 40 m/s

e. more that 40 m/s

7. A Doppler effect occurs when a source of sound moves
a. toward you.

b. away from you.

c. both of these.

d. none of these.

8. Suppose that some of a wave’s energy dissipates over time. In time, this will reduce the wave’s
a. speed

b. wavelength

c. amplitude

d. frequency

e. period

9. A sound source vibrating at a high frequency emits a high
a. speed.

b. amplitude.

c. pitch.

d. all of these.

10. The range of human hearing is
a. from about 10Hz to 10,000Hz

b. from about 20Hz to 20,000Hz

c. from about 40Hz to 40,000Hz

d. greater than about 20,000Hz

e. less than about 20Hz

11. The source of all wave motion is

a) a harmonic object, or system of objects.

b) a region of high and low pressures.

c) something vibrating.

d) transverse motion.

e) any energy source.

12. Frequency and period are related, in that they are
a) both on the same wavelength.

b) two expressions for much the same thing.

c) None of these.

d) inverses of each other.

e) directly proportional to each other.

13. What is the wave speed for a wave of 2 meters wavelength that has a frequency of 3 hertz?
a) 3 m/s.

b) 6 m/s.

c) 19 m/s.

d) 9 m/s.

e) 2 m/s.

14. A transverse wave typifies light, and a longitudinal wave typifies
a) All of these.

b) sound.

c) radio waves.

d) earthquake waves.

e) infra-red waves.

15. Wave interference is characteristic of what type of the waves listed below?
a) Transverse waves.

b) No waves, but vibrations.

c) Longitudinal waves.

d) All waves.

16. Consider a wave that travels a distance of 3 meters in 1 second with a frequency of 2 hertz. What is its amplitude?
a) 1 meter.

b) 4 meters.

c) 2 meters.

d) Not enough information is given.

e) 3 meters.

17. When a fire engine approaches you with its siren blasting away, sound waves passing you have an increased
a) speed.

b) Neither.

c) frequency.

d) Both.

18. A sonic boom is produced by an aircraft when it
a) flies faster than sound continuously.

b) None of these.

c) pulls out of a subsonic dive.

d) first exceeds the speed of sound and breaks the sound barrier.

e) All of these.

Need more examples or assistance? If you have a new text book then you may be able to access tutorials and online quizes at www.MasteringPhysics.com. The Access Code for this site is normally included in the first few pages of the book. Also, SFA physics major Rusty Permenter is available in the AARC for physics help between 6 and 8pm on Mondays. See Dr. B for help during these office hours.

Your Name:	e.g. John Doe
Your Campus ID:	e.g. 12345678
Your SFA Email Address:	e.g. doejd@titan.sfasu.edu
Due Date	9/11/2007 11:00PM

1. Which of the following is not a medium which will transmit sound? a. solids b. liquids c. gasses d. vacuum
2. Two waves having the same amplitude and frequency interfere as a crest meets a trough. The result will be _____. a. constructive interference b. destructive interference c. resonance d. standing waves
3. What is the frequency of a simple pendulum if its period is 20 seconds? a. 0.1 Hz b. 50 Hz c. 0.05 Hz d. you can't get frequency from period
4. The vibrations of a longitudinal wave move in a direction a. along the direction of the wave travel b. at right angles to the direction of wave travel
5. A node is a position of a. minimum amplitude b. maximum amplitude c. medium amplitude
6. A floating leaf oscillates up and down two complete cycles in one second as a water wave passes by. The wave’s wavelength is 10 meters. What is the wave’s speed? a. 2 m/s b. 10 m/s c. 20 m/s d. 40 m/s e. more that 40 m/s
7. A Doppler effect occurs when a source of sound moves a. toward you. b. away from you. c. both of these. d. none of these.
8. Suppose that some of a wave’s energy dissipates over time. In time, this will reduce the wave’s a. speed b. wavelength c. amplitude d. frequency e. period
9. A sound source vibrating at a high frequency emits a high a. speed. b. amplitude. c. pitch. d. all of these.
10. The range of human hearing is a. from about 10Hz to 10,000Hz b. from about 20Hz to 20,000Hz c. from about 40Hz to 40,000Hz d. greater than about 20,000Hz e. less than about 20Hz

11. The source of all wave motion is a) a harmonic object, or system of objects. b) a region of high and low pressures. c) something vibrating. d) transverse motion. e) any energy source.
12. Frequency and period are related, in that they are a) both on the same wavelength. b) two expressions for much the same thing. c) None of these. d) inverses of each other. e) directly proportional to each other.
13. What is the wave speed for a wave of 2 meters wavelength that has a frequency of 3 hertz? a) 3 m/s. b) 6 m/s. c) 19 m/s. d) 9 m/s. e) 2 m/s.
14. A transverse wave typifies light, and a longitudinal wave typifies a) All of these. b) sound. c) radio waves. d) earthquake waves. e) infra-red waves.
15. Wave interference is characteristic of what type of the waves listed below? a) Transverse waves. b) No waves, but vibrations. c) Longitudinal waves. d) All waves.
16. Consider a wave that travels a distance of 3 meters in 1 second with a frequency of 2 hertz. What is its amplitude? a) 1 meter. b) 4 meters. c) 2 meters. d) Not enough information is given. e) 3 meters.
17. When a fire engine approaches you with its siren blasting away, sound waves passing you have an increased a) speed. b) Neither. c) frequency. d) Both.
18. A sonic boom is produced by an aircraft when it a) flies faster than sound continuously. b) None of these. c) pulls out of a subsonic dive. d) first exceeds the speed of sound and breaks the sound barrier. e) All of these.