One Parsec is a unit of astronomical distance. It is defined as the distance at which a radius of one astronomical unit (AU) subtends an angle of one second of arc. One parsec is approximately equal to: MCQ with Answer and Explanation

Question

One Parsec is a unit of astronomical distance. It is defined as the distance at which a radius of one astronomical unit (AU) subtends an angle of one second of arc. One parsec is approximately equal to:

A. 3.26 light years

B. 1.5 x 10^11 meters

C. 9.46 x 10^15 meters

D. 3.0 x 10^8 meters

Answer: Option A

Solution (By JKSSB Mock Tests)

The parsec (parallax second) is the largest standard unit of distance used in astronomy. 1 Astronomical Unit (AU) is approx 1.5 x 10^11 m. 1 Light Year (ly) is approx 9.46 x 10^15 m. 1 Parsec is approximately 3.08 x 10^16 m. Converting parsecs to light years: (3.08 x 10^16) / (9.46 x 10^15) ≈ 3.26 light years.

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