Question

The farthest objects (known as quasars) in our universe are so distant that light emitted by them takes billion of years to reach the earth. What is the distance in km of a quasar from which light takes 3.0 billion years to reach us?

Answer 1

Answer:

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Time taken by quasar light to reach Earth = 3 billion years

= 3 x 109 years

= 3 x 109 x 365 x 24 x 60 x 60 s

Speed of light = 3 x 108 m/s

Distance between the Earth and quasar

= (3 x 108) x (3 x 109 x 365 x 24 x 60 x 60)

= 283824 x 1020 m

= 2.8 x 1022 km