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प्रश्न
Which of the following methods can be used to measure the speed of light in laboratory?
विकल्प
Roemer method
Fizeau method
Foucault method
Michelson method
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उत्तर
Foucault method
Foucault gave the first laboratory method to find the velocity of light. He obtained a value of \[2 . 98 \times {10}^8 \text { m/s }\] from his measurements.
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संबंधित प्रश्न
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| A ray of light travels from a denser to a rarer medium. After refraction, it bends away from the normal. When we keep increasing the angle of incidence, the angle of refraction also increases till the refracted ray grazes along the interface of two media. The angle of incidence for which it happens is called critical angle. If the angle of incidence is increased further the ray will not emerge and it will be reflected back in the denser medium. This phenomenon is called total internal reflection of light. |
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| A ray of light travels from a denser to a rarer medium. After refraction, it bends away from the normal. When we keep increasing the angle of incidence, the angle of refraction also increases till the refracted ray grazes along the interface of two media. The angle of incidence for which it happens is called critical angle. If the angle of incidence is increased further the ray will not emerge and it will be reflected back in the denser medium. This phenomenon is called total internal reflection of light. |
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