Wave Optics - SS1 Physics Past Questions and Answers - page 2
Discuss the different types of interference patterns that can be observed in the interference of light waves.
The interference of light waves can result in various types of interference patterns. Some commonly observed patterns include:
- a) Young's Double-Slit Interference: This pattern occurs when light waves pass through two closely spaced slits. It produces a series of alternating bright and dark fringes on a screen, known as interference fringes. The pattern is characterised by equally spaced fringes, with the central fringe being the brightest.
- b) Thin Film Interference: This pattern occurs when light waves reflect off or transmit through a thin film of material. It results in the formation of coloured fringes or bands, known as Newton's rings or thin-film interference fringes. The colours observed are due to the interference between the reflected or transmitted waves.
In Young's double-slit experiment, interference patterns are observed due to the:
Diffraction of light
Dispersion of light
Reflection of light
Interference of light
In Young's double-slit experiment, the bright and dark fringes observed on the screen are a result of:
Constructive and destructive interference
Diffraction of light
Reflection of light
Dispersion of light
The condition for maximum constructive interference in Young's double-slit experiment is when the path difference between the two slits is:
Zero
Half the wavelength
Equal to the wavelength
An integer multiple of the wavelength
If the distance between the slits in Young's double-slit experiment is decreased, what happens to the interference fringes observed on the screen?
The fringes become wider
The fringes become narrower
The fringes disappear
The fringes remain the same
In Young's double-slit experiment, if the distance between the screen and the slits is increased, what happens to the spacing between the interference fringes?
The spacing between the fringes increases
The spacing between the fringes decreases
The spacing between the fringes remains the same
The fringes disappear
In Young's double-slit experiment, if monochromatic light is replaced with white light, what happens to the interference pattern observed on the screen?
The interference pattern becomes more distinct
The interference pattern becomes less distinct
The interference pattern disappears
The interference pattern remains the same
If the width of each slit in Young's double-slit experiment is increased, what happens to the interference pattern observed on the screen?
The interference pattern becomes more distinct
The interference pattern becomes less distinct
The interference pattern disappears
The interference pattern remains the same
In Young's double-slit experiment if coherent sources of light are used, what happens to the visibility of the interference pattern?
The visibility increases
The visibility decreases
The visibility remains the same
The interference pattern disappears
Explain Young's double-slit experiment and how it demonstrates the wave nature of light.
Young's double-slit experiment is a famous experiment that provides evidence for the wave nature of light. In this experiment, a coherent light source is directed towards a barrier with two small slits. The light passing through the slits creates two coherent sources of light that act as separate wavefronts. These waves then overlap and interfere with each other, resulting in an interference pattern of bright and dark fringes on a screen placed behind the slits.
The presence of these interference fringes demonstrates that light behaves as a wave, exhibiting constructive and destructive interference. This experiment supports the wave theory of light and confirms that light can exhibit interference patterns, similar to other wave phenomena.