Which of the following is due to inhomogeneous refractive index of earth’s atmosphere?
Show Hint
- Red colour of the evening Sun.
- Blue colour of the sky.
- Oval shape of the evening Sun.
- Large apparent size of the evening Sun.
The Correct Option is C
Solution and Explanation
The inhomogeneous refractive index of the atmosphere causes the light rays to bend as they pass through different layers of the atmosphere. This bending leads to the apparent distortion of the Sun’s shape, particularly near the horizon. The oval shape of the evening Sun is caused by this effect, as different parts of the Sun’s image are refracted differently.
Step 2: Conclusion.
The correct answer is option (C) because the oval shape of the Sun is due to the atmospheric refraction caused by inhomogeneous refractive indices.
Top Questions on Optics
- An equilateral prism is made of a material of refractive index \( \sqrt{2} \). Find the angle of incidence for minimum deviation of the light ray.
Light from a point source in air falls on a spherical glass surface (refractive index, \( \mu = 1.5 \) and radius of curvature \( R = 50 \) cm). The image is formed at a distance of 200 cm from the glass surface inside the glass. The magnitude of distance of the light source from the glass surface is 1cm.
- A transparent film of refractive index 2.0 is coated on a glass slab of refractive index 1.45. What is the minimum thickness of transparent film to be coated for the maximum transmission of green light of wavelength 550 nm?
- In a Young's double slit experiment, the source is white light. One of the slits is covered by red filter and another by green filter. In this case,
- Two concave refracting surfaces of equal radii of curvature and refractive index 1.5 face each other in air as shown in figure. A point object O is placed midway, between P and B. The separation between the images of O, formed by each refracting surface is:
Questions Asked in IIT JAM exam
- If \(\left(\frac{1-i}{1+i}\right)^{n/2} = -1\), where \(i = \sqrt{-1}\), one possible value of n is
- IIT JAM PH - 2025
- Complex numbers
- In a two-level atomic system, the excited state is 0.2 eV above the ground state. Considering the Maxwell-Boltzmann distribution, the temperature at which 2% of the atoms will be in the excited state is _____ K. (up to two decimal places)
(Boltzmann constant \(k_B = 8.62 \times 10^{-5}\) eV/K)
- IIT JAM PH - 2025
- Mechanics
At a particular temperature T, Planck's energy density of black body radiation in terms of frequency is \(\rho_T(\nu) = 8 \times 10^{-18} \text{ J/m}^3 \text{ Hz}^{-1}\) at \(\nu = 3 \times 10^{14}\) Hz. Then Planck's energy density \(\rho_T(\lambda)\) at the corresponding wavelength (\(\lambda\)) has the value \rule{1cm}{0.15mm} \(\times 10^2 \text{ J/m}^4\). (in integer)
[Speed of light \(c = 3 \times 10^8\) m/s]
(Note: The unit for \(\rho_T(\nu)\) in the original problem was given as J/m³, which is dimensionally incorrect for a spectral density. The correct unit J/(m³·Hz) or J·s/m³ is used here for the solution.)- IIT JAM PH - 2025
- Mechanics
- The ratio of the density of atoms between the (111) and (110) planes in a simple cubic (sc) lattice is ____. (up to two decimal places)
- IIT JAM PH - 2025
- Solid State Physics, Devices, Electronics
- The packing fraction for a two-dimensional hexagonal lattice having sides 2r with atoms of radii r placed at each vertex and at the center is _____. (up to two decimal places)
- IIT JAM PH - 2025
- Solid State Physics, Devices, Electronics