Science 1120 Physical Science Spring 2008: questions and topics for Test 3.

Questions for Thought

1. How did the wave nature of matter first originate?
2. What was Aristotle’s philosophy on the wave nature of matter?
3. What Galileo and Leonardo Da Vinci contribute to understanding waves?
4. What is Mersenne’s law?
5. How factors determine the fundamental frequency of a vibrating string?
6. What is meant by the harmonics of a vibrating string?
7. Who made the first attempts to measure the speed of sound in air?
8. Who showed that a vibrating string could be made to vibrated at more than one frequency at the same time leading to a better understanding of musical instruments?
9. What is the relationship between frequency, pitch, amplitude, and loudness?
10. How is the frequency of a wave calculated from the period?
11. What is the difference between a transverse wave and a compression wave?
12. What type of material can a transverse or compression wave propagate through?
13. How does the speed of sound vary in gases, liquids, and solid? Explain.
14. How are scientists using sound waves to measure temperature changes in oceans?
15. What is a sonic boom and when was the speed of sound first surpassed?
16. What is meant by resonance in sound?
17. What is the difference between closed tubes and open tubes in producing resonant sounds?
18. How is the frequency of a tuning fork measured with a tube in a container of water?
19. What is the difference between a C played with a tuning fork and with a violin?
20. How are beats generated?
21. What is the decibel scale for sound generation?
22. What is the difference between a 60 dB and 80 dB sound?
23. Why was Galileo unable to measure the speed of light?
24. How was Jupiter used to measure the speed of light for the first time in 1676?
25. How does light propagate through a vacuum?
26. Who discovered infrared radiation?
27. What are the various types of radiation that are part of the electromagnetic spectrum?
28. What is the Doppler Effect and how is it used today?
29. What are the laws of Reflection and Refraction?
30. What is meant by the index of refraction of a substance?
31. What is the property of diamond that makes them sparkle so much in such dazzling colors?
32. How is a rainbow produced?
33. How was the wave nature of light first demonstrated by Thomas Young?
34. What is meant by Poisson’s spot?
35. What is diffraction?
36. What is the difference between polarized and non-polarized light? Give examples.
37. How do polarizing sunglasses reduce glare?
38. What is the difference between a diverging lens and converging lens?
39. What conditions are required to produce a real image? A virtual image?
40. How does the lens in the eye function to focus on images at different distances?
41. When were eye glasses first developed?
42. What types of lenses are prescribed for nearsightedness and farsightedness?

Problems for Review

1. Which one of the following travels at 300,000,000 m/sec?

a. Sound waves in air.

b. Sonar.

c. Microwave radiation.

d. Waves produced by a sonic boom.

e. Ultrasonic

2. An increase of 20 dB increases the sound intensity by a factor of

a. 10.

b. 20

c. 100.

d. 1000.

e. 10000.

3. An object is 5 cm from a converging lens with a focal length of 10 cm. The image is:

a. inverted and real.

b. erect and real.

c. erect and virtual.

d. inverted and virtual.

e. enlarged, inverted, and virtual.

4. Longitudinal waves cannot be

a. reflected.

b. refracted.

c. diffracted.

d. polarized.

5. The intensity of a 100-dB sound is doubled. What is the new intensity of the sound in dB?

a. 53 dB

b. 97 dB

c. 103 dB

d. 120 dB

e. 200 dB

6. How many times greater is the speed of blue light (l = 400 nm) than the speed of infrared light (l = 1000 nm) in vacuum?

a. The two types of light travel at the same speed.

b. 0.4 times

c. 1.6 times

d. 2.5 times

e. 1000 times

7. The property of a sound wave that is closely related to its loudness is

a. amplitude.

b. speed.

c. frequency.

d. wavelength.

8. A Doppler blue shift indicates

a. a shift toward longer wavelengths.

b. a shift toward lower frequencies.

c. that a light source is moving away from you.

d. that the light source is moving towards you.

e. a, b, and c are all correct

9. What of the following differences between Light waves and sound waves are correct?

a. Light can travel in a vacuum and sound waves can not travel in a vacuum.

b. Light travels much faster than sound waves.

c. Sound waves are longitudinal waves and Light waves are transverse waves.

d. a, b, and c are all correct.

10. Wave frequency is inversely proportional to

a. amplitude.

b. period.

c. wave velocity.

d. wave speed.

11. A laser light of wavelength l =630 nm passes through a slit of width d. What slit width would produce the largest amount of diffraction?

a. d = 500 nm.

b. d = 630 nm.

c. d = 700 nm.

d. d = 800 nm.

12. Polarized sunglasses operate on the principle that

a. natural light is polarized and reflected light is unpolarized.

b. natural light is unpolarized and reflected light is polarized.

c. both natural and reflected light are polarized.

d. both natural and reflected light are unpolarized.

13. Compared to visible radiation, ultraviolet radiation

a. has shorter wavelengths and lower energy.

b. has longer wavelengths and lower energy.

c. has shorter wavelengths and higher energy.

d. has longer wavelengths and faster velocity.

e. travels at much lower speed than ultraviolet radiation.

14. A wave with a frequency of 10 Hz will have a period of ___________ second(s).

a. 0.1

b. 0.2

c. 0.5

d. 1.0

e. 10.0

15. An object is 20 cm from a converging lens with a focal length of 5 cm. The image is:

a. smaller, inverted, and real.

b. smaller, erect, and real.

c. enlarged, erect, and virtual.

d. smaller, erect, and real.

e. enlarged, inverted, and virtual.

16. One person talking loudly in a room is about 70 dB. If 100 people in the room are all talking at the same level the intensity is now:

a. 80 dB.

b. 90 dB

c. 100 dB

d. 120 dB

e. 170 dB

17. The major difference between transverse and longitudinal waves is the

a. direction of the wave motion.

b. direction of the particle displacement.

c. direction of the particle displacement with respect to the direction of wave motion.

d. phase difference.

18. Primary rainbows occur when:

a. two internal reflections of light with refraction occur in raindrops

b. light refracts through ice crystals

c. a single internal reflection of light with refraction occurs in raindrops

d. light refracts through a cloud of large raindrops when you are looking at the Sun

e. the sun disappears behind a cloud and then reappears

19. What is the primary difference between the sound produced by a middle-C played with a piano and with a tuning fork?

a. The tuning fork only vibrates at the fundamental frequency

b. The tuning fork and the piano both sound exactly the same

c. The tuning fork is entirely metal and thus louder.

d. The Piano is more expensive and therefore better sounding

e. A tuning fork cannot be produced that plays middle-C

20. Longitudinal waves can propagate through which of the following

a. gases only

b. liquids only

c. solids only

d. solids and gases only

e. solids and liquids only

f. liquids, solids, and gases

21. A sound produces an intensity of 1 W/m2 at a distance of 10 m from a source. What would be the intensity a distance of 20 m from the source?

a. 4 W/m2

b. 2 W/m2

c. 1 W/m2..

d. 0.5 W/m2.

e. 0.25 W/m2

22. Active noise control involves:

a. the muffling of sound with thick ear muffs

b. the damping of noise using laser beams.

c. the principle of superposition of waves to cancel to noise

d. the use of light waves to cancel the noise.

e. the principle of total internal reflection

23. What is the frequency of red light that has a wavelength of 600 nm?

a. 3.0 x 10⁸ Hz

b. 5 x 10¹⁴ Hz

c. 3 x 10²⁶ Hz

d. 2 x 10³ Hz

e. 60 Hz

24. A train whistle emits a sound with a frequency of 500 Hz when standing in the station. If the same whistle is blown when it is moving toward the station at 40 mph what will be the approximate frequency someone standing at the station will hear?

a. 380 Hz.

b. 480 Hz.

c. 500 Hz.

d. 520 Hz.

e. 1000 Hz.

25. A person hears thunder from a lightning strike 1 second after the flash. How far away did the lightning occur?

a. 0.2 miles

b. 0.4 miles

c. 1.0 miles

d .2.0 miles

e. 5.0 miles

26. A stretched string has a second harmonic frequency of 200 Hz. What is the frequency of the fundamental?

a. 100 Hz

b. 150 Hz

c. 200 Hz

d. 300 Hz

e. 400 Hz

27. A stretched string has a second harmonic frequency of 200 Hz. What is the frequency of the third harmonic?

a. 100 Hz

b. 150 Hz

c. 200 Hz

d. 300 Hz

e. 400 Hz

28. Which one of the following uses sound waves?

a. Sonar

b. Radar

c. Doppler Radar

d. Microwaves

e. Lasers.

29. A sound wave with a frequency of 1 kHz has a wavelength of 34 mm. What is the wavelength of a sound wave with a frequency of 10 kHz?

a. 3.4 mm

b. 34 mm.

c. 3.4 nm.

d. 3.4 m.

e. 34 m.

30. What type of lens is used for a person who is nearsighted?

a. concave

b. convex

c. diffraction

d. reflective

e. combination of convex and reflective

31. What is the wavelength of radio waves with a frequency of 1 MHz?

a. 3 m

b. 30 m

c. 300 m

d. 3,000 m

e. 30,000 m

32. A simple magnifying glass has a focal length of 6.0 cm. An object is placed 5.0 cm from it. (Determine the image distance)

a.       -30 cm

b.       5 cm

c.       10 cm

d.       15 cm

33. A simple magnifying glass has a focal length of 6.0 cm. An object is placed 15.0 cm from it. Determine the image distance

a.       3.75 cm

b.       5 cm

c.       10 cm

d.       15 cm

e.       16 cm

34. A simple magnifying glass has a focal length of 10.0 cm. An object is placed 20.0 cm from it. Determine the magnification

a. +10

b. +5

c. +2

d. -1

e. -5

35. A wave traveling in a medium has a speed of 10 m/s and a wavelength of 2.0 m. What is the frequency of the waves in the medium?

0.2 Hz.

0.5 Hz

1.0 Hz.

5.0 Hz.

20.0 Hz.

36. Which one of the following has the lowest index of refraction?

a. zirconium

b. water

c. glass

d. diamond.

37. A ray of visible light passes from glass into air at an angle of incidence of 20 deg. What will be the angle of refraction?

a. 30 deg.

b. 20 deg.

c. 15 deg.

d. 13 deg.

e. 10 deg.

38. Sunlight that passes through a prism is broken into a rainbow spectrum light because:

a. of total internal reflection.

b. of regular reflection

c. the index of refraction depends upon wave amplitude.

d. the index of refraction depends upon the wavelength.

39. The trapping of light in "light pipes," or fiber optics, is due to

a. total internal reflection.

b. refraction.

c. diffraction.

d. absorption of the outside light.

40. A particular material has an index of refraction of 2.0. What is the speed of light in the material?

a. 2.0 x 10³ m/s

b. 1.5 x 10⁸ m/s

c. 2.0 x 10⁸ m/s

d. 3.0 x 10⁸ m/s

e. 6.0 x 10⁸ m/s