You are given kerosene, turpentine and water. In which of these does the light travel fastest? Use the information given in the table.
ScienceClass 10CBSEAnswered 27 Mar 2026
Answer
|
Material medium |
Refractive index |
Material medium |
Refractive index |
|
Air |
1.0003 |
Canada Balsam |
1.53 |
|
Ice |
1.31 |
– |
– |
|
Water |
1.33 |
Rock salt |
1.54 |
|
Alcohol |
1.36 |
– |
– |
|
Kerosene |
1.44 |
Carbon disulphide |
1.63 |
|
Fused quartz |
1.46 |
Dense flint glass |
1.65 |
|
Turpentine oil |
1.47 |
Ruby |
1.71 |
|
Benzene |
1.50 |
Sapphire |
1.77 |
|
Crown glass |
1.52 |
Diamond |
2.42 |
Answer-
Light travels faster in water as compared to kerosene & turpentine, as the refractive index of water is lower than that of kerosene and turpentine. The speed of light is inversely proportional to the refractive index.
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