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Assertion : Just before setting, the sun...

Assertion `:` Just before setting, the sun may appear to be elliptical. This happens due to refraction.
Reason `:` Refraction of light ray through the atmosphere may cause different magnification in mutually perpendicular directions.

A

If both assertion and reason are true and reason is the correct explanation of assertion.

B

If both assertion and reason are true but reason is not the correct explanation of assertion.

C

If assertion is true but reason is false.

D

If assertion and reason both are false.

Text Solution

Verified by Experts

The correct Answer is:
A
When the sun is close to setting, refraction will effect the top part of the sun differently from the bottom half. The top half will radiate its image truly, while the bottom portion will send an apparent image. Since the bottom portion of sun is being seen through thicker, more dense atmosphere, the bottom image is being bent intensely and gives the impression of being squashed or ''flattened'' or elliptical shape.
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Negative Refractive Index: One of the most fundamental phenomena in optics is refraction. When a beam of light crosses the interface between two different materials, its path is altered depending on the difference in the refractive indices of the materials. The greater the difference, the greater the refraction of the beam. For all known naturally occurring materials the refractive index assumes only positive values. But does this have to be the case? In 1967, Soviet physicist Victor Veselago hypothesized that a material with a negative refractive index could exist without violating any of the laws of physics. Veselago predicted that this remarkable material would exhibit a wide variety of new optical phenomena. However, until recently no one had found such a material and Veselago's ideas had remained untested. Recently, meta-material samples are being tested for negative refractive index. But the experiments show significant losses and this could be an intrinsic property of negative index materials. Snell's law is satisfied for the material having a negative refractive index, but the direction of the refracted light ray is 'mirror-imaged about the normal to the surface. There will be an interesting difference in image formation if a vessel is filled with "negative water" having refractive index - 1.33 instead of regular water having refractive index 1.33. Say, there is a fish in a vessel filled with negative water. The position of the fish is such that the observer cannot see it due to normal refraction since the refracted ray does not reach to his eye. But due to negative refraction, he will be able to see it since the refracted ray now reaches his eye. A ray in incident on normal glass and. "Inegative glass" at an angle 60^@ . If the magnitude of angle of refraction in normal glass is 45^@ then, what will be the magnitude of angle of refraction in the "negative glass"?

Negative Refractive Index: One of the most fundamental phenomena in optics is refraction. When a beam of light crosses the interface between two different materials, its path is altered depending on the difference in the refractive indices of the materials. The greater the difference, the greater the refraction of the beam. For all known naturally occurring materials the refractive index assumes only positive values. But does this have to be the case? In 1967, Soviet physicist Victor Veselago hypothesized that a material with a negative refractive index could exist without violating any of the laws of physics. Veselago predicted that this remarkable material would exhibit a wide variety of new optical phenomena. However, until recently no one had found such a material and Veselago's ideas had remained untested. Recently, meta-material samples are being tested for negative refractive index. But the experiments show significant losses and this could be an intrinsic property of negative index materials. Snell's law is satisfied for the material having a negative refractive index, but the direction of the refracted light ray is 'mirror-imaged about the normal to the surface. There will be an interesting difference in image formation if a vessel is filled with "negative water" having refractive index - 1.33 instead of regular water having refractive index 1.33. Say, there is a fish in a vessel filled with negative water. The position of the fish is such that the observer cannot see it due to normal refraction since the refracted ray does not reach to his eye. But due to negative refraction, he will be able to see it since the refracted ray now reaches his eye. When the angle of incidence will be equal to angle of refraction for material having negative refraction index?

A2Z-GEOMETRICAL OPTICS-Section B - Assertion Reasoning
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