Why is polaris used as a celestial reference point?

1 answer:

8 0

At the equator, the North Celestial and South Celestial Poles would lie on the horizon where the meridian intersects the horizon. Polaris is called the "North Star." ... Polaris is special because the Earth's North Pole points almost exactly towards it.

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Answer

given,

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thickness of film= 10⁻⁴ cm

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b) phase difference is equal to

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