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प्रश्न
Solve the following example.
Speed in first medium, v1 = 3 × 108 m/s
Speed in second medium, v2 = 2 × 108 m/s
Then 2n1 = ?
उत्तर
Given: Speed of light in first medium (v1) = 3 × 108 m/s,
Speed of light in second medium (v2) = 2 × 108 m/s
To find: Refractive index of the second medium with respect to the first medium (2n1)
Formula: 2n1 = `"v"_1/"v"_2`
Calculation: From formula,
2n1 = `(3 xx 10^8)/(2 xx 10^8)` = 1.5
Refractive index of the second medium with respect to the first medium (2n1) is 1.5.
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संबंधित प्रश्न
How refraction of light is related to refractive index?
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(i) vacuum,
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The refractive index of diamond is 2.42. What is the meaning of this statement?
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(b) 3 × 108 mm/s
(c) 3 × 108 km/s
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(c) does not get refracted
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The speed of light in vacuum and in two different glasses is given in the table below:
| Medium | Speed of light |
| Vacuum | 3.00 × 108 m/s |
| Flint glass | 1.86 × 108 m/s |
| Crown glass | 1.97 × 108 m/s |
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(b) Calculate the relative refractive index for light going from crown glass to flint glass.
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(b) Q
(c) R
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| Column ‘A’ | Column ‘B’ |
| Refractive index of water | (a) 1.31 |
| (b) 1.36 | |
| (c) 1.33 |
What happens when a light ray passes from a rarer medium to a denser medium?
Match the pair:
| Group 'A' | Group 'B' | |
| Substance | Refractive index | |
| Air | (a) | 1.33 |
| (b) | 1.46 | |
| (c) | 1.0003 |
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| The ability of medium to refract light is expressed in terms of its optical density. Optical density has a definite connotation. It is not the same as mass density. On comparing two media, the one with the large refractive index is optically denser medium than the other. The other medium with a lower refractive index is optically rarer. Also the speed of light through a given medium is inversely proportional to its optical density. |
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(a) Which one of the two optically denser and why?
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OR
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- Complete the ray diagram of the above scenario when the light ray comes out of the plastic block from the top flat end.
