119 practice sets · Page 1 of 6
Coherent light of a single frequency passes through a double slit with a separation d, to produce a pattern on a screen as distance D from the slits. What would cause the separation between adjacent minima on the screen to increase?
increase the index of refraction of the medium in which the setup is immersed
increase the separation d between the slits
increase the distance
increase the frequency of the incident light
as the order increases, the width of a dark band in diffraction patterns
Increases
Decreases
Does not change
becomes infinity
As a wave travels down a spring, the amplitude slowly decreases. Why does this occur?
The law of conservation of energy does not apply to waves.
The energy is spread out along the entire length of the spring.
The wave slows down as it travels along the spring.
Some energy is lost due to friction as the particles in the spring rub against each other
Antireflection coating is helps in which case of the following?
Minimizing the reflection of light from top surface
To absorb and control the amount of light entering into the medium
To allow maximum light to reflect from top surface
To allow minimum light to enter into the medium
An index of refraction less than one for a medium would imply
Refraction is not possible
Reflection is not possible
That the speed of light in the medium is the same as the speed of light in vacuum
That the speed of light in the medium is greater than the speed of light in vacuum
A wedge shaped thin has
Zero thickness at both ends
Thickness increase and decrease alternately
Non-uniform thickness
Zero thickness at one end and it increasing towards other end
A wavelength is commonly measured in which one of the following units?
Electron volts
Seconds
Radians
Angstroms
A thin film is observed in white light. The color of the film seen at a particular point depends upon
Distance of the source
Brightness of the source
Location of observer
Width of the source
A slit of width a is illuminated by white light. For what value of a will the first minimum for red light fall at an angle of 300 wavelength of red light is 6500 Ao
1.3 X 10-4cm
1.6 X 10-4 cm
cm
1.4 X 10-4cm
A monochromatic (single frequency, single wavelength) light ray in air (n = 1) enters a glass prism (n = 1.5). In the glass prism
The frequency is the same, but the wavelength is smaller than in air
The wavelength is the same, but the frequency is greater than in air
Both the frequency and the wavelength are the same as in air
The frequency is the same, but the wavelength is greater than in air
A grating has 6000 lines per cm. How many orders of light of wavelength 4500 Ao can be seen?
3
4
1
2
A film is said to be thin if its thickness is
Of the order of nanometer (10-9 m)
Of the order of Pico meter (10-12 m)
Much smaller than wavelength of light
Comparable with one wavelength of light
A diffraction grating is optically equivalent to a multiple slit system in which the number of slit, N is typically
5000/cm
1000/cm
2000/cm
3000/cm
A color with a wavelength longer than that of yellow is
Violet
Green
Red
Blue
A beam of white light is passed through a diffraction grating and the resulting spectrum is allowed to fall on a screen. Which one of the following is the color of light that undergoes the greatest deviation from its original direction? Is it
Blue
violet
Red
yellow
A beam of light is incident on a large block of glass. The index of refraction of the glass is greater than one. Is the wavelength of the light in the glass?
The same as the wavelength of the light in the air?
None of above
Longer than
Shorter than
X-ray diffraction can be observed by using
Convex lens
Michelsons interferometer
Diffraction Grating
Rock salt crystal
Why in Newtons rings the center spot is always dark?
The thickness of the film is zero at center
The path difference between incident ray and reflected ray is 1/2 wavelength
The incident ray and reflected ray undergo destructive interference
All of above
Why in Newtons rings setup, the beam splitter (mirror) is kept at 450?
It allows light rays to incident at 450 over the top surface of Planoconvex lens
It allows light rays to incident uniformly over the top surface of Planoconvex lens
It allows light rays to incident parallel over the top surface of Planoconvex lens
It allows light rays to incident at 900 over the top surface of Planoconvex lens
Whose principle or law states that each point on a wave front may be considered a new wave source? Is it
Snells Law
Huygenss Principle
Youngs Law
Hertzs Law
