Advertisements
Advertisements
Question
Monochromatic light of wavelength 4300 Å falls on a slit of width ‘a’. For what value of ‘a’ the first maximum falls at 30° ?
Advertisements
Solution
`λ = 4300 Å `
`= 4300 xx10^-10 m`
a = ?
n = 1
`sin θ = L/a `
`therefore a = λ / sin 30 = (4300xx10 ^-10)/(1/2)`
`a= 4300xx10^-10xx2`
`= 8600 xx10^-10 m`
for first maximum
`sin θ = (n+1/2)λ/a`
`= 3/2 xx (4300xx10^-10)/(1/2)= 1.29 µ"m"`
APPEARS IN
RELATED QUESTIONS
In the diffraction pattern due to a single slit of width 'd' with incident light of wavelength 'λ', at an angle of diffraction θ. the condition for first minimum is ....
(a)`lambda sin theta =d`
(b) `d costheta =lambda`
(c)`d sintheta=lambda`
(d) `lambda cos theta=d`
For a single slit of width "a", the first minimum of the interference pattern of a monochromatic light of wavelength λ occurs at an angle of λa. At the same angle of λa, we get a maximum for two narrow slits separated by a distance "a". Explain.
Two wavelengths of sodium light of 590 nm and 596 nm are used in turn to study the diffraction taking place at a single slit of aperture 2 × 10−6 m. The distance between the slit and the screen is 1·5 m. Calculate the separation between the positions of first maxima of the diffraction pattern obtained in the two cases.
Explain two types of diffraction of light.
Show graphically the intensity distribution in Fraunhofer's single slit diffraction experiment. Label the axes.
Draw the intensity distribution for the diffraction bands produced due to single slit ?
Two wavelengths of sodium light 590 nm and 596 nm are used, in turn to study the diffraction taking place at a single slit of aperture 2 × 10−4m. The distance between the slit and the screen is 1.5 m. Calculate the separation between the positions of the first maxima of the diffraction pattern obtained in the two cases.
Two wavelengths of sodium light 590 nm and 596 nm are used, in turn, to study the diffraction taking place due to a single slit of aperture 1 × 10−4 m. The distance between the slit and the screen is 1.8 m. Calculate the separation between the positions of the first maxima of the diffraction pattern obtained in the two cases.
In a single slit diffraction experiment, how does the angular width of the central maxima change when:
- screen is moved away from the plane of the slit?
- width of the slit is increased?
- light of larger wavelength is used?
What should be the order of obstacle or aperture for diffraction of light?
Wavelength of light of frequency 100 Hz is
The penetration of light into the region of geomaterial shadow is called.
The magnifying power of a telescope in normal adjustment is 24, when the length of the telescope tube 1 meter. The focal length of the eye lens is
Diffraction effects are easy to notice in the case of sound waves than in case of light waves because
Direction of the first secondary maximum in the Fraunhoffer diffraction pattern at a single slit is given by (a is the width of the slit):
Which of the following device is used to study the spectra of light?
Consider the diffraction pattern for a small pinhole. As the size of the hole is increased ______.
- the size decreases.
- the intensity increases.
- the size increases.
- the intensity decreases.
Four identical monochromatic sources A, B, C, D as shown in the (Figure) produce waves of the same wavelength λ and are coherent. Two receiver R1 and R2 are at great but equal distances from B.
- Which of the two receivers picks up the larger signal?
- Which of the two receivers picks up the larger signal when B is turned off?
- Which of the two receivers picks up the larger signal when D is turned off?
- Which of the two receivers can distinguish which of the sources B or D has been turned off?
Write two points of difference between an interference pattern and a diffraction pattern.
How can you differentiate whether a pattern is produced by a single slit or double slit?
Derive the expression for the angular position of (i) bright and (ii) dark fringes produced in a single slit diffraction.
In a diffraction pattern due to a single slit, how will the angular width of the central maximum change, if orange light is used in place of green light?
Justify your answer.
In a diffraction pattern due to a single slit, how will the angular width of the central maximum change, if the screen is moved closer to the slit?
Justify your answer.
In a diffraction pattern due to a single slit, how will the angular width of the central maximum change, if the slit width is decreased?
Justify your answer.
In the diagram shown, the separation between the slit is equal to 3λ, where λ is the wavelength of the light incident on the plane of the slits. A thin film of thickness 3λ and refractive index 2 has been placed in the front of the upper slit. The distance of the central maxima on the screen from O is ______.
