In a franhofer diffraction experiment at a single slit using a light of wavelength 400 nm, the first minimum is formed at an angle of 30. The direction of the first secondary maximum is given […]
A parallel beam of fast moving electrons is incident normally on a narrow slit. A flourescent screen is placed at a large distance from the slit. If the speed of the electrons is increased, then […]
When we close one slit in the young’s double slit experiment, then
Options
(a) the bandwidth increased (b) the bandwidth is decreased (c) the interference pattern is shifted (d) the diffraction pattern is observed
λ₁ and λ₂ are used to illuminate the slits. β₁ and β₂ are the corresponding fringe widths. The wavelength λ₁ can produce photoelectric effect when incident on a metal. But the wavelength λ₂ cannot produce […]
Light of wavelength λ from a point source falls on a small circular obstacle of diameter d. Dark and bright circular rings around a central bright spot are formed on a screen beyond the obstacle. […]
A polarised light of intensity I₀ is passed through another polariser whose pass axis makes an angle of 60⁰ with the pass axis of the former. What is the intensity of emergent polarised light from […]
The angle of incidence at which reflected light is totally polarised for refraction from air to glass (refractive index μ) is
Options
(a) sin⁻¹μ (b) sin⁻¹(1/μ) (c) tan⁻¹(1/μ) (d) tan⁻¹(μ)
Correct Answer:
tan⁻¹(μ)
Colours appear on a thin soap film and soap bubbles due to the phenomenon of
Options
(a) interference (b) scattering (c) diffraction (d) dispersion
Correct Answer:
interference
Explanation:
No explanation available. Be the […]
In the Young’s double slit experiment, the intensity of light at a point on the screen (where the path difference is λ) is K, (λ being the wavelength of light used). The intensity at a […]
Wavefront is the locus of all points, where the particles of the medium vibrate with the same
Options
(a) phase (b) amplitude (c) frequency (d) period
Correct Answer:
phase
Explanation:
On the wave front, […]
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