Question
If light takes 8 minutes to travel from the Sun to Earth , and over 4 hours to travel from the'Sun to the planet Neptune , what is the distance from the Sun to Neptune? 5 AU 3 AU 5 ly 30 ly 30 AU
Solution
4.6
(332 Votes)
Xavier
Veteran ยท Tutor for 10 years
Answer
Here's how to figure out the distance to Neptune:1. **Find the ratio of travel times:** Neptune's travel time (4 hours) is 30 times longer than Earth's travel time (8 minutes = 8/60 hours = 2/15 hours). 4 hours / (2/15 hours) = 302. **Relate travel time to distance:** Since light travels at a constant speed, the distance is directly proportional to the travel time. Therefore, Neptune is 30 times farther from the Sun than Earth is.3. **Use the Earth-Sun distance:** The Earth-Sun distance is defined as 1 Astronomical Unit (AU).4. **Calculate Neptune's distance:** Neptune's distance is 30 times the Earth-Sun distance, so it's 30 AU.Therefore, the correct answer is
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