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What is speed of light in vacuum?...

What is speed of light in vacuum?

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The speed of light in vacuum is known to be almost exactly 300,000 km per second.
In 1665 the Danish astronomer of Roemer first estimated the speed of light by observing one of the twelve moons of the planet Jupiter.
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A new unit of length is chosen such that the speed of light in vacuum is unity. The distance between the Sun and the Earth in terms of the new unit, if light takes 8 minute and 20 sec to cover the distance is .............

The ratio of speed of light in vacuum to the speed of light in medium is defined as _________ .

Knowledge Check

  • The ratio of speed of light in vaccum to the speed of light medium is __________ .

    A
    velocity
    B
    reflective index
    C
    refractive index
    D
    scattering property.

  • Planck’s constant (h), speed of light in vacuum (c) and Newton’s gravitational constant (G) are taken as three fundamental constants. Which of the following combinations of these has the dimension of length?

    A
    `(sqrt(hG))/(c^((3)/(2)))`
    B
    `(sqrt(hG))/(c^((3)/(2)))`
    C
    `sqrt((hc)/(G))`
    D
    `sqrt((G c)/(h^((3)/(2))))`

  • Planck's constant (h), speed of light in vacuum (c) and Newton's gravitational constant (G) are taken as three fundamental constants. Which of the following combinations of these has the dimension of length ?

    A
    `(sqrt(hG))/(c^(3/2))`
    B
    `(sqrt(hG))/(c^(5/2))`
    C
    `sqrt((hc)/(G))`
    D
    `sqrt((Gc)/(h^(3/2))`

    • Similar Questions

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    Explain how Corpuscular theory predicts the speed of light in a medium, say, water, to be greater than the speed of light in vacuum. Is the prediction confirmed by experimental determination of the speed of light in water? If not, which alternative picture of light is consistent with experiment?

    A new unit of length is chosen such that the speed of light in vscuum is unity. What is the distance between the sun and the Earth in terms of the new unit if light takes 8 min and 20 s to cover this distance.

    What is the speed of light in diamond if its refractive index is 2.41 ?

    a. The refractive index is glass is 1.5. What is the speed of light in glasss? (Speed of light invacuum is 3.0xx10^(8)ms^(-1) ) b. Is the speed of light inglass independent of he colour of light? If not, which of the two colours red and violet travels slower in a glass prism?

    Plank's constant (h), speed of light in vacuum (c) and Newton's gravitational constant (G) are taken as three fundamental constants. Which of the following combinations of these has the dimensions of length?

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