Calculate the distance of a quasar from which light takes 2 billion years to reach the earth.explain the method.
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Light travels 300,000 km/second. A year is composed of 365 days (except leap years). Each day is 24 hours with 60 minutes each and 60 seconds a piece. You could do this the easy way or the hard way. The hard way is to say "distance = speed X time", which means determining how many seconds are in 2 billion years then multiplying by the speed of light.
That's way too hard.
1 "Lightyear" is the DISTANCE light travels in 1 year. Therefore, if a beam of light from a quasar takes 2 billion years to reach earth, the quasar would be "2 Light Years away".
Just for craps and giggles, this amounts to 18,920,000,000,000 kilometers or almost 19 trillion miles away!
That's way too hard.
1 "Lightyear" is the DISTANCE light travels in 1 year. Therefore, if a beam of light from a quasar takes 2 billion years to reach earth, the quasar would be "2 Light Years away".
Just for craps and giggles, this amounts to 18,920,000,000,000 kilometers or almost 19 trillion miles away!
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Light travels at 300,000,000 m/s, so convert 2,000,000,000 years to seconds and multiply.
2x10^9 years = 6.31x10^16 sec.
(3x10^8 m/s)*(6.31x10^16 sec) = 1.91x10^25 m
2x10^9 years = 6.31x10^16 sec.
(3x10^8 m/s)*(6.31x10^16 sec) = 1.91x10^25 m