1. constructive interference. destructive interference.
Q35.1
Two sources S1 and S2 oscillating in phase emit sinusoidal waves. Point P is 7.3 wavelengths from source S1 and 4.3 wavelengths from source S2. As a result, at point P there is
constructive interference.
destructive interference.
constructive interference at certain times and destructive interference at other times.
neither constructive nor destructive interference.
Not enough information is given to decide.
Answer: A

2. A35.1
Two sources S1 and S2 oscillating in phase emit sinusoidal waves. Point P is 7.3 wavelengths from source S1 and 4.3 wavelengths from source S2. As a result, at point P there is
constructive interference.
destructive interference.
constructive interference at certain times and destructive interference at other times.
neither constructive nor destructive interference.
Not enough information is given to decide.

3. constructive interference. destructive interference.
Q35.2
Two sources S1 and S2 oscillating in phase emit sinusoidal waves. Point P is 7.3 wavelengths from source S1 and 4.6 wavelengths from source S2. As a result, at point P there is
constructive interference.
destructive interference.
constructive interference at certain times and destructive interference at other times.
neither constructive nor destructive interference.
Not enough information is given to decide.
Answer: D

4. A35.2
Two sources S1 and S2 oscillating in phase emit sinusoidal waves. Point P is 7.3 wavelengths from source S1 and 4.6 wavelengths from source S2. As a result, at point P there is
constructive interference.
destructive interference.
constructive interference at certain times and destructive interference at other times.
neither constructive nor destructive interference.
Not enough information is given to decide.

5. The bright areas move closer together.
Q35.3
In Young’s experiment, coherent light passing through two slits (S1 and S2) produces a pattern of dark and bright areas on a distant screen. If the wavelength of the light is increased, how does the pattern change?
The bright areas move closer together.
The bright areas move farther apart.
The spacing between bright areas remains the same, but the color changes.
In any of the above ways, depending on circumstances.
In none of the above ways.
Answer: B

6. A35.3
In Young’s experiment, coherent light passing through two slits (S1 and S2) produces a pattern of dark and bright areas on a distant screen. If the wavelength of the light is increased, how does the pattern change?
The bright areas move closer together.
The bright areas move farther apart.
The spacing between bright areas remains the same, but the color changes.
In any of the above ways, depending on circumstances.
In none of the above ways.

7. three half-wavelengths three quarter-wavelengths
In Young’s experiment, coherent light passing through two slits (S1 and S2) produces a pattern of dark and bright areas on a distant screen. What is the difference between the distance from S1 to the m = +3 bright area and the distance from S2 to the m = +3 bright area?
six wavelengths
three wavelengths
three half-wavelengths
three quarter-wavelengths
Not enough information is given to decide.
Answer: B

8. A35.4
In Young’s experiment, coherent light passing through two slits (S1 and S2) produces a pattern of dark and bright areas on a distant screen. What is the difference between the distance from S1 to the m = +3 bright area and the distance from S2 to the m = +3 bright area?
six wavelengths
three wavelengths
three half-wavelengths
three quarter-wavelengths
Not enough information is given to decide.

9. Q35.5
Two radio antennas radiating in phase are located at points A and B, which are 6 wavelengths apart. A radio receiver is moved along a line from point B to point C. At what distances from point B will the receiver detect an intensity maximum? A B C
Answer: D
D. both A and B
E. all of A, B, and C

10. A35.5
Two radio antennas radiating in phase are located at points A and B, which are 6 wavelengths apart. A radio receiver is moved along a line from point B to point C. At what distances from point B will the receiver detect an intensity maximum? A B C
D. both A and B
E. all of A, B, and C

11. Q35.6
An air wedge separates two glass plates as shown. Light of wavelength strikes the upper plate at normal incidence. At a point where the air wedge has thickness t, you will see a bright fringe if t equals
Answer: B
D. either A or C.
E. any of A, B, or C.

12. A35.6
An air wedge separates two glass plates as shown. Light of wavelength strikes the upper plate at normal incidence. At a point where the air wedge has thickness t, you will see a bright fringe if t equals
D. either A or C.
E. any of A, B, or C.

13. more than one of the above
Q35.7
A thin layer of turpentine (n = 1.472) lies on top of a sheet of ice (n = 1.309). It is illuminated from above with light whose wavelength in turpentine is 400 nm. Which of the following possible thicknesses of the turpentine layer will maximize the brightness of the reflected light?
100 nm
200 nm
300 nm
400 nm
more than one of the above
Answer: E

14. A35.7
A thin layer of turpentine (n = 1.472) lies on top of a sheet of ice (n = 1.309). It is illuminated from above with light whose wavelength in turpentine is 400 nm. Which of the following possible thicknesses of the turpentine layer will maximize the brightness of the reflected light?
100 nm
200 nm
300 nm
400 nm
more than one of the above

15. a point that is 1.00 10–7 m closer to one slit than the other
Q-RT35.1
A two-slit interference experiment uses coherent light of wavelength –7 m. Rank the following points in the interference pattern according to the intensity at each point, from highest to lowest.
a point that is –7 m closer to one slit than the other
a point that is –7 m closer to one slit than the other
a point where the light waves received from the two slits are out of phase by 0.250π rad
a point where the light waves received from the two slits are out of phase by 0.400π rad
Answer: ACDB

16. A-RT35.1
A two-slit interference experiment uses coherent light of wavelength –7 m. Rank the following points in the interference pattern according to the intensity at each point, from highest to lowest.
a point that is –7 m closer to one slit than the other
a point that is –7 m closer to one slit than the other
a point where the light waves received from the two slits are out of phase by 0.250π rad
a point where the light waves received from the two slits are out of phase by 0.400π rad
Answer: ACDB