The distance to the nearest large spiral galaxy,the Andromeda galaxy,is 2.4 × 10²² m.How long does it take light to travel from Andromeda to us? A)4.4 years B)360 years C)1.2 thousand years D)2.5 million years E)4.5 billion years

Question

Quizplus · Accepted Answer

To calculate the time it takes for light to travel from Andromeda to us, we can use the formula: distance = speed x time, where speed of light = 3 x 10^8 m/s.

Thus, time = distance / speed of light = (2.4 x 10^22 m) / (3 x 10^8 m/s) = 8 x 10^13 seconds. 
Converting seconds to years gives: (8 x 10^13 seconds) / (60 sec/min x 60 min/hr x 24 hr/day x 365.25 days/year) ≈ 2.5 million years.

Therefore, the best choice is D, 2.5 million years.

The Distance to the Nearest Large Spiral Galaxy,the Andromeda Galaxy,is