Question

The closest star to our solar system is Alpha Centauri, which is 4.12 × 10^16 m away. How long would it take light from Alpha Centauri to reach our solar system if the speed of light is 3.00 × 10^8 m/s? (Provide an answer in both seconds and in years.)
(According to the textbook the answer is 4.35 years, i'm just not sure how to get there as I keep getting a different answer)

Answer 1

Time = (distance) / (speed)

Time = (4.12x10^16 m) / (3 x10^8 m/s)

Time = 1.37 x 10^8 seconds

Divide the seconds by 86,400 to get days. Then divide the days by 365 to get years.

Time = about 4.35 years