Wave Optics Questions and Answers

The distance between identical parts of a wave (crest to crest) is called its Select one: a. frequency b. the amplitude c. wavelength d. period
Physics
Wave Optics
The distance between identical parts of a wave (crest to crest) is called its Select one: a. frequency b. the amplitude c. wavelength d. period
A demonstration of interference is done in class. A Slinky" is stretched out from end to end. Three cups are placed on the ground, positioned just to the side of the Slinky". Two pulses are introduced into each end at the same time. The pulses travel towards each other as shown in the diagram.
What will be observed after the pulses pass by each other?
Select one:
a. All three cups will be knocked over.
b. Nothing will happen to any of the cups; they will all be left standing.
c. Cups 1 and 3 will be knocked over; cup 2 will be left standing.
d. Only cup 2 will be knocked over, cups 1 and 3 will be left standing.
Physics
Wave Optics
A demonstration of interference is done in class. A Slinky" is stretched out from end to end. Three cups are placed on the ground, positioned just to the side of the Slinky". Two pulses are introduced into each end at the same time. The pulses travel towards each other as shown in the diagram. What will be observed after the pulses pass by each other? Select one: a. All three cups will be knocked over. b. Nothing will happen to any of the cups; they will all be left standing. c. Cups 1 and 3 will be knocked over; cup 2 will be left standing. d. Only cup 2 will be knocked over, cups 1 and 3 will be left standing.
Which lists the correct steps that occur when using a diffraction grating to bend light? 
diffracted wavelengths reach the eyes → different wavelengths of light bend at different angles → the eyes see different colors → light strikes the grooves 
different wavelengths of light bend at different angles → light strikes the grooves → diffracted wavelengths reach the eyes→ the eyes see different colors 
diffracted wavelengths reach the eyes → the eyes see different colors → light strikes the grooves → different wavelengths of light bend at different angles 
light strikes the grooves → different wavelengths of light bend at different angles → diffracted wavelengths reach the eyes→ the eyes see different colors
Physics
Wave Optics
Which lists the correct steps that occur when using a diffraction grating to bend light? diffracted wavelengths reach the eyes → different wavelengths of light bend at different angles → the eyes see different colors → light strikes the grooves different wavelengths of light bend at different angles → light strikes the grooves → diffracted wavelengths reach the eyes→ the eyes see different colors diffracted wavelengths reach the eyes → the eyes see different colors → light strikes the grooves → different wavelengths of light bend at different angles light strikes the grooves → different wavelengths of light bend at different angles → diffracted wavelengths reach the eyes→ the eyes see different colors
If laser light is reflected from each of the items below, a diffraction pattern appears. The pattern arises because all these devices contain parallel tracks of information that act as a reflection diffraction grating. Which device results in diffraction maxima that are farther apart?
Physics
Wave Optics
If laser light is reflected from each of the items below, a diffraction pattern appears. The pattern arises because all these devices contain parallel tracks of information that act as a reflection diffraction grating. Which device results in diffraction maxima that are farther apart?
A laser has a wavelength of 581 nm. A grating and a lens are used to split the beam into three parallel beams spaced 1.85 cm apart. If the slit spacing is 1.00 μm, what focal length lens should be used?
Physics
Wave Optics
A laser has a wavelength of 581 nm. A grating and a lens are used to split the beam into three parallel beams spaced 1.85 cm apart. If the slit spacing is 1.00 μm, what focal length lens should be used?
When a real image is formed by a diverging lens, which of the following statements are true
The sign of image position (s') will have a negative value
The image must be magnified in size
The image must be inverted
The image can be observed on a screen
This type of image cannot be formed by this type of lens.
The image must be diminished in size
Physics
Wave Optics
When a real image is formed by a diverging lens, which of the following statements are true The sign of image position (s') will have a negative value The image must be magnified in size The image must be inverted The image can be observed on a screen This type of image cannot be formed by this type of lens. The image must be diminished in size
Three electromagnetic waves E₁ = Eosinwt, E₂ = Epcoswt and E3 = 2Eosin(wt + π) are superimposed at a point. If intensity due to wave E₁ at that point is lo. then resultant intensity at this point comes out Klo, find the value of k.
Physics
Wave Optics
Three electromagnetic waves E₁ = Eosinwt, E₂ = Epcoswt and E3 = 2Eosin(wt + π) are superimposed at a point. If intensity due to wave E₁ at that point is lo. then resultant intensity at this point comes out Klo, find the value of k.
A soap film (n=1.33) in the air is 270 nm thick. If it is illuminated with white light at normal incidence what colour will it appear to be in reflected light?
Green light
White light
Blue light
Red light
Physics
Wave Optics
A soap film (n=1.33) in the air is 270 nm thick. If it is illuminated with white light at normal incidence what colour will it appear to be in reflected light? Green light White light Blue light Red light
8. When light travels from air to an unknown material at an incident angle of 50°, it is refracted at an angle of 30°. What will be the critical angle for this material if it is placed in water? (Use 1.33 for the refractive index of water.)
a) 54.6°
b) 66.9°
c) 60.2°
d) 0°
e) 49.6°
Physics
Wave Optics
8. When light travels from air to an unknown material at an incident angle of 50°, it is refracted at an angle of 30°. What will be the critical angle for this material if it is placed in water? (Use 1.33 for the refractive index of water.) a) 54.6° b) 66.9° c) 60.2° d) 0° e) 49.6°
Light of wavelength 631 nm passes through a
diffraction grating having 299 lines/mm.
For related problem-solving tips and strategies, you
may want to view a Video Tutor Solution of Width of
a grating spectrum.
Part A
What is the total number of bright spots (indicating complete constructive
interference) that will occur on a large distant screen? Solve this problem without
finding the angles. (Hint: What is the largest that sin can be? What does this imply
for the largest value of m?)
Physics
Wave Optics
Light of wavelength 631 nm passes through a diffraction grating having 299 lines/mm. For related problem-solving tips and strategies, you may want to view a Video Tutor Solution of Width of a grating spectrum. Part A What is the total number of bright spots (indicating complete constructive interference) that will occur on a large distant screen? Solve this problem without finding the angles. (Hint: What is the largest that sin can be? What does this imply for the largest value of m?)
Red light of wavelength 633 nm from a helium-neon laser passes through a slit 0.330 mm wide. The diffraction pattern is observed on a screen 3.15 m away. Define the width of a bright fringe as the distance between the minima on either side. 
What is the width of the central bright fringe? 
Express your answer in meters. 
What is the width of the first bright fringe on either side of the central one? 
Express your answer in meters.
Physics
Wave Optics
Red light of wavelength 633 nm from a helium-neon laser passes through a slit 0.330 mm wide. The diffraction pattern is observed on a screen 3.15 m away. Define the width of a bright fringe as the distance between the minima on either side. What is the width of the central bright fringe? Express your answer in meters. What is the width of the first bright fringe on either side of the central one? Express your answer in meters.
A massless elastic cord (that obeys Hooke's law) will break if the tension in the cord exceeds Tmax. One end of the cord is attached to a fixed
point, the other is attached to an object of mass 3m as shown in the figure. If a second, smaller object of mass m moving at an initial speed
Vo strikes the larger mass and the two stick together, the cord will stretch and break, but the final kinetic energy of the two masses will be
zero. If instead the two collide with a perfectly elastic one dimensional collision, the cord will still break and the larger max. will move off with
final speed of v₁. All motion occurs on a horizontal frictionless surface. (assume the Hooke's law is obeyed throughout until the cord breaks)
m
3m
Find the ratio of the total kinetic energy of the system of two masses after the perfectly elastic collision and the cord has broken to the initial
kinetic energy of the smaller mass prior to the collison
Physics
Wave Optics
A massless elastic cord (that obeys Hooke's law) will break if the tension in the cord exceeds Tmax. One end of the cord is attached to a fixed point, the other is attached to an object of mass 3m as shown in the figure. If a second, smaller object of mass m moving at an initial speed Vo strikes the larger mass and the two stick together, the cord will stretch and break, but the final kinetic energy of the two masses will be zero. If instead the two collide with a perfectly elastic one dimensional collision, the cord will still break and the larger max. will move off with final speed of v₁. All motion occurs on a horizontal frictionless surface. (assume the Hooke's law is obeyed throughout until the cord breaks) m 3m Find the ratio of the total kinetic energy of the system of two masses after the perfectly elastic collision and the cord has broken to the initial kinetic energy of the smaller mass prior to the collison
A ray of light travels from air into another medium, making an angle of θ₁ = 45.0° with the normal as in the figure below.
(a) Find the angle of refraction 02 if the second medium is sodium chloride.
(b) Find the angle of refraction 02 if the second medium is polystyrene.
(c) Find the angle of refraction 02 if the second medium is glycerine.
Physics
Wave Optics
A ray of light travels from air into another medium, making an angle of θ₁ = 45.0° with the normal as in the figure below. (a) Find the angle of refraction 02 if the second medium is sodium chloride. (b) Find the angle of refraction 02 if the second medium is polystyrene. (c) Find the angle of refraction 02 if the second medium is glycerine.
A photon with wavelength λ = 0.0580 nm is incident on an electron that is initially at rest.

If the photon scatters in the backward direction, what is the magnitude of the linear momentum of the electron just after the collision with the photon?
Physics
Wave Optics
A photon with wavelength λ = 0.0580 nm is incident on an electron that is initially at rest. If the photon scatters in the backward direction, what is the magnitude of the linear momentum of the electron just after the collision with the photon?
During takeoff, the sound intensity level of a jet engine is 170 dB at a distance of 28 m.
Part A
What is the sound intensity level at a distance of 1.0 km?
Express your answer to two significant figures and include the appropriate units.
Physics
Wave Optics
During takeoff, the sound intensity level of a jet engine is 170 dB at a distance of 28 m. Part A What is the sound intensity level at a distance of 1.0 km? Express your answer to two significant figures and include the appropriate units.
One of the wavelengths of light emitted by hydrogen atoms under normal laboratory conditions is at λ = 656.3 nm in the red portion of the electromagnetic spectrum. In the light emitted from a distant galaxy this same spectral line is observed to be Doppler-shifted to λ = 954.7 nm, in the infrared portion of the spectrum. 
Part A 
How fast are the emitting atoms moving relative to the earth? Express your answer in meters per second to three significant figures.
Physics
Wave Optics
One of the wavelengths of light emitted by hydrogen atoms under normal laboratory conditions is at λ = 656.3 nm in the red portion of the electromagnetic spectrum. In the light emitted from a distant galaxy this same spectral line is observed to be Doppler-shifted to λ = 954.7 nm, in the infrared portion of the spectrum. Part A How fast are the emitting atoms moving relative to the earth? Express your answer in meters per second to three significant figures.
In a two slit experiment with monochromatic light, fringes are obtained on a screen placed at some distance from the slits. If the screen is moved by a distance of 5 × 10-2 m towards the slits, the change in the fringe width is 3 × 10-² m. If the separation between the slits is 10-³ m, the wavelength of light used is
A. 5 x 10^-7m
B. 6 x 10^-7m
C. 7 x 10^-7m
D. 6 × 10^-6 m
Physics
Wave Optics
In a two slit experiment with monochromatic light, fringes are obtained on a screen placed at some distance from the slits. If the screen is moved by a distance of 5 × 10-2 m towards the slits, the change in the fringe width is 3 × 10-² m. If the separation between the slits is 10-³ m, the wavelength of light used is A. 5 x 10^-7m B. 6 x 10^-7m C. 7 x 10^-7m D. 6 × 10^-6 m
A radio station utilizes frequencies between commercial AM and FM. What is the frequency (in megahertz) of a 11.60 m wavelength channel?

               MHz
Physics
Wave Optics
A radio station utilizes frequencies between commercial AM and FM. What is the frequency (in megahertz) of a 11.60 m wavelength channel? MHz
A 4500 lines/cm grating is illuminated by a single wavelength laser. What is the wavelength of this laser if the location of the second order maximum is at an angle of 42° with respect to the central maxima
A. 370 nm
B. 430 nm
C. 580 nm
D. 740 nm
Physics
Wave Optics
A 4500 lines/cm grating is illuminated by a single wavelength laser. What is the wavelength of this laser if the location of the second order maximum is at an angle of 42° with respect to the central maxima A. 370 nm B. 430 nm C. 580 nm D. 740 nm
Assume a "vertical polarizer" transmits vertically polarized light. If a perfectly horizontally polarized light goes through a vertical polarizer, how much of the original light comes out?
A. half
B. none
C. all
D. not enough info
Physics
Wave Optics
Assume a "vertical polarizer" transmits vertically polarized light. If a perfectly horizontally polarized light goes through a vertical polarizer, how much of the original light comes out? A. half B. none C. all D. not enough info
What is the wavelength of light falling on double slits separated by 2.01 μm, if the third-order minimum is at an angle of 58.0°?
Physics
Wave Optics
What is the wavelength of light falling on double slits separated by 2.01 μm, if the third-order minimum is at an angle of 58.0°?