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प्रश्न
The wavefronts of light coming from a distant source of unknown shape are nearly _________ .
पर्याय
plane
elliptical
cylindrical
spherical
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उत्तर
plane
Wave travelling from a distant source always has plane wavefront.
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संबंधित प्रश्न
Let us list some of the factors, which could possibly influence the speed of wave propagation:
(i) Nature of the source
(ii) Direction of propagation
(iii) Motion of the source and/or observer
(iv) Wavelength
(v) Intensity of the wave
On which of these factors, if any, does the speed of light in vacuum?
The wavefronts of a light wave travelling in vacuum are given by x + y + z = c. The angle made by the direction of propagation of light with the X-axis is _________ .
In the figure, the optical fibre is l = 2 m long and has a diameter of d = 20 µm. If a ray of light is incident on one end of the fibre at angle θ1 = 40°, the number of reflections it makes before emerging from the other end is close to:
(Refractive index of fibre is 1.31 and sin 40° = 0.64)
A glass slab of thickness 4 cm contains the same number of waves as 5 cm of water. When both are traversed by the same monochromatic light. If the refractive index of water is `(4/3)`. What is that of glass?
White light is an incident at 20° on a material of silicate flint glass slab as shown. `μ_"violet"` = 1.66 and µr = 1.6. For what value of d will the separation be 1 mm in red and violet rays?
A light ray in a medium (RI = 5/3) enters another medium at an angle of 30°. The angle in the other medium is sin-1 (5/6). The incident angle must be increased such that the ray is completely reflected at minimum degrees is ______.
Which principle can be used to derive the laws of refraction?
What does \[\frac{\sin i}{\sin r}\] equal in terms of the speeds in the two media?
Which equation is Snell's law of refraction for media 1 and 2?
Which expression gives the wavelength of light in medium 2?
How are the wavelengths in the two media related to the speeds of light in those media?
What happens to the wavelength of light when it goes from a rarer to a denser medium?
How does the speed of light in a denser medium compare with its speed in a rarer medium?
Which picture of light was needed to address why its speed differs between media?
How does the wave picture's conclusion about the speed of light in a denser medium compare with that deduced from the particle picture?
