Waves Study Guide Part II

AP Physics B

Waves Study Guide Part II

For your convenience, Part I of Waves is reprinted on the very last page of this document. It contains a reminder of crucial wave ideas from when waves were studied in general, much of which hasn’t been done in class since the non-AP Physics class.

Part II is all about wave ideas in relation to light. This document does not chart the existence of Geometric Optics Ideas from Chapter 22 and 23, but they are obviously crucial, and there is a practice test here related to them.

Part II Topics

Textbook content: Read Chapter 24

Textbook problems: 35 through 43 odd in Chapter 24, any odd problem after #57

Realize that a variety of physical phenomena that are explained by this theory, rainbows on soap bubbles for example.

Copy #

Version A

Official Physics Quiz

INTERFERENCE AND DIFFRACTION OF LIGHT

This booklet contains 20 multiple choice questions worth 1 point each. Use the Scantron sheet supplied as your answer sheet. If you wish to you may use scratch paper and a computation aid (i.e., a calculator, slide rule, abacus, or perhaps even a brain). Otherwise this quiz is closed book, closed notes, and definitely closed neighbor. Do NOT mark on this booklet in any way. If you do, a humongous horde of handsome, hairless hottentots will hustle you to Hollywood for a public humiliation.

When you finish the quiz, put your answer sheet inside this booklet and place the booklet on Mr. McGehee's desk in the front of the room in the version A or version B pile.

934

Equations - Chapter 19 Quiz

10-9 meter = 1 nanometer

f = 1/T v = l/T = fl vlight = 3 x 108 m/s

l = Dxd/L or l = xd/L = d sin q

l = xw/L = w sin q

l = xd/L = d sin q

Quiz Chapter 19 - INTERFERENCE AND DIFFRACTION OF LIGHT

Directions: Each of the questions or incomplete statements below is followed by four or five suggested answers or completions. There is only one correct choice. Select the one that is best in each case.

1. The wavelengths of visible light are in a range closest to

A. the thickness of a sheet of paper. D. your height.

B. the diameter of your thumb. E. the length of a football field.

C. your belt size.

2. Which of the following statements concerning blue and red light is true?

A. Red light has a longer wavelength and higher frequency than blue light.

B. Red light has a shorter wavelength and higher frequency than blue light.

C. Red light has a longer wavelength and lower frequency than blue light.

D. Red light has a shorter wavelength and lower frequency than blue light.

E. none of these

3. The visible portion of the electromagnetic spectrum has wavelengths ranging from about 4 x 10-7 to 7 x 10-7 meter. The human eye is most sensitive to wavelengths in the yellow-green part of the visible spectrum around 5.6 x 10-7 meter. The frequency of this yellow-green light is

A. 1.9 x 10-15 Hz B. 5.9 x 10-3 Hz C. 170 Hz

D. 5.4 x 1014 Hz E. none of these

4. The wavelength of the yellow-green light in question #3 in units of nanometers is

A. 0.056 nm B. 0.56 nm C. 56.0 nm D. 560 nm E. none of these

The following information relates to questions 5 through 11.

Light from a monochromatic source of wavelength of 6 x 10-7 meter is incident on two narrow parallel slits that are 2 x 10-4 meter apart. After passing through the two slits the light forms a two-slit interference pattern on a screen 4 meters from the slits.

5. The path difference for light traveling from the two slits to the first bright line from the center line on the screen is

A. l/2 B. l C. 3l/2 D. 2l E. 5l/2

6. Which of the answers in question #5 is the path difference for light traveling from the two slits to the second dark line from the center line?

7. The spacing of the lines of maximum brightness on the screen is

A. 2.4 x 10-11 m B. 6.0 x 10-7 m C. 1.2 x 10-2 m

D. 8.3 x 102 m E. none of these

05/A

Quiz Chapter 19 - INTERFERENCE AND DIFFRACTION OF LIGHT

8. If the wavelength of the incident light is doubled, the spacing of the bright lines in the pattern will

A. be increased by a factor of 2. D. be increased by a factor of 22.

B. be decreased by a factor of 1/2. E. be decreased by a factor of 1/(22).

C. remain unchanged.

9. If the frequency of the incident light is doubled, the spacing of the dark lines in the pattern will (choose from the answers in question #8)

10. If the distance between the slits is decreased from d to d/2, the spacing of the bright lines in the pattern will (choose from the answers in question #8)

11. If the screen is moved closer to the slits, the spacing of the dark lines will

A. decrease B. increase C. remain the same

12. In an experiment sources of white light, red light, and blue light are viewed first through a single narrow slit, then through two narrow parallel slits. Which of the following are observed in BOTH patterns?

i. When white light is viewed, colors were seen in the pattern.

ii. All nodal lines are equally spaced.

iii. The nodal line spacing is greater in the red pattern than in the blue pattern.

A. iii only B. i, ii, & iii C. ii & iii only D. i & ii only E. i & iii only

13. A single narrow slit is placed between a yellow light source and a screen resulting in a single slit diffraction pattern being formed on the screen. Which of the following changes would cause the width of the central maximum and the nodal line spacing to decrease?

i. Increase the width of the slit

ii. Use red light instead of yellow

iii. Use a higher frequency light source

A. i, ii, & iii B. i & iii only C. ii & iii only D. i & ii only E. none of them

0. The intensity (brightness) of light passing through a single slit is measured as a function of the distance on either side of the center line. A graph of the data is shown at the right. The figures below show some of the different paths taken by the light as it leaves the slit. Which of the figures shows the path that accounts for the minimum of

intensity at point X?

05A

Quiz Chapter 19 - INTERFERENCE AND DIFFRACTION OF LIGHT

15. Yellow light is incident on a single slit that is 3 x 10-5 meter wide. A single slit pattern of bright and dark lines is formed on a screen 0.6 meter from the slit. In the pattern the first dark line is 0.012 meter from the center of the central maximum. The wavelength of the light is

A. 60 nm B. 240 nm C. 500 nm D. 900 nm E. none of these

16. White light is viewed through a diffraction grating and is dispersed into a color spectrum. The color seen in the spectrum farthest from the light source is

A. red B. orange C. yellow D. green E. violet

17. For an experiment, a student can choose between two diffraction gratings; one has 5000 lines/cm and the other 7500 lines/cm. If a monochromatic light source is to be viewed through the grating, which one of the following will be true?

A. When viewed through the 5000 line/cm grating, the light will be seen farthest

from the center line.

B. When viewed through the 7500 line/cm grating, the light will be seen farthest

from the center line.

C. The light will be seen at the same position through either grating.

18. A diffraction grating with 5000 lines/cm has an average line spacing of 2 x10-6 meter. If 500 nanometer monochromatic light is passed through the grating, how far from the centerline will the first-order image appear on a screen placed 2 meters from the grating?

A. 5 x 10-1 m B. 5 x 10-4 m C. 5 x 10-13 m D. 2 m E. none of these

19. Two light waves from different sources arrive at the same point at the same time and their amplitudes add algebraically according to the principle of superposition. This is called

A. Dispersion B. Refraction C. Diffraction D. Interference E. Polarization

20. A hologram is

A. a photographic image taken with light from a laser that has been passed

through two sheets of crossed Polaroid.

B. a complex interference pattern recorded on photographic film.

C. a photographic record of light from a laser that has been passed through a high quality diffraction grating.

D. a photographic image of a double slit interference pattern.

05/A

Quiz Ch. 19 - INTERFERENCE AND DIFFRACTION OF LIGHT Version A Answers

1. A

2. C

3. D

4. D

5. B

6. C

7. C

8. A

9. B

10. A

11. A

12. E

13. B

14. D

15. E Ans: 600 nm

16. A

17. B

18. A

19. D

20. B

Copy #

Version A

Official Physics Quiz

Chapters 22, 23

REFLECTION AND REFRACTION OF LIGHT

When you finish the quiz, put your answer sheet inside this booklet and place the booklet on Mr. McGehee's desk in the front of the room in the version A or version B pile.

934

Equations - Chapter 16, 17, & 18 Quiz

vlight = 3 x 108 m/s

Quiz Chapters 16, 17, & 18 - REFLECTION AND REFRACTION OF LIGHT

1. Light waves are thought to be transverse waves because

A. they can be focused by a lens.

B. they exhibit interference effects.

C. they undergo refraction when passing from one medium to another.

D. they diffract around objects.

E. they can be polarized.

2. The property of light waves that is associated with color is

A. their amplitude B. their frequency C. their intensity

D. their speed E. the fact that light can be polarized

3. As shown in the diagram at the right, a beam of light reflects between two plane mirrors which are mounted perpendicular to one another. The beam strikes the first with an incident angle of 35o and reflects toward the other mirror. The reflected beam then strikes the second mirror at point P with an incident angle qi. The angle of reflection, qr, at point P will be

A. 35o B. 55o C. 70o D. 90o E. none of these

4. If light passes from air into glass, the index of refraction is found to be 1.5. If the speed of light in air is 3 x 108 m/s, the speed of light in the glass is about

A. 1 x 108 m/s B. 1.5 x 108 m/s C. 2 x 108 m/s D. 3 x 108 m/s E. 4.5 x 108 m/s

5. The drawing at the right represents light rays from a very distant source entering a plano-convex lens. The lens is made of glass and is submerged in a liquid having a greater optical density than glass. Which of the following best represents the path of the upper light ray as it passes through the lens?

05/A.1

Quiz Chapters 16, 17, & 18 - REFLECTION AND REFRACTION OF LIGHT

The following diagram and information relate to Questions 6, 7, and 8.

In the diagram at the right AB is the boundary between

medium I and medium II. MN is the normal to the boundary at point P.

6. If HP is an incident monochromatic (one color) light ray and PQ is the refracted ray, which of the following statement(s) is/are true?

i. qi is greater than qr.

ii. The index of refraction for light passing from medium I into medium II is greater than 1.

iii. Medium I is of lower optical density than medium II.

iv. The wavelength of the light increases as it crosses the boundary.

v. The speed of the light increases as it crosses the boundary.

A. i, ii, & iii only B. iii, iv, & v only C. i, iii, & iv only D. iv & v only

E. none of these combinations are correct

7. Assume medium I is air and medium II is water. If KP is the incident ray, the refracted ray is most represented by ray

A. PU B. PV C. PT D. PG E. PR

8. Assume medium I is air and medium II is glass. If VP is the incident ray and angle VPN is greater than the critical angle, the ray leaving point P will most likely be

A. PK B. PJ C. PF D. PQ E. PB

9. A light ray is incident along the normal to side AC of a right angle glass prism as shown at the right. The index of refraction for a ray passing from air into the glass is 1.5. Which one of the

following statements is true?

A. The ray is totally reflected from side AB with a reflected

angle greater than 10o.

B. The ray emerges from side BC with an angle of refraction

greater than 45o.

C. The ray emerges from side BC with an angle of refraction less than 45o.