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?
A) 5 AU
B) 30 AU
C) 30 ly
D) 5 ly
E) 0.6 ly

Question

Quizplus · Accepted Answer

The distance between the sun and Neptune can be calculated using the speed of light, which is approximately 299,792,458 meters per second. 
Let's convert the 8 minutes it takes for light to travel from the sun to Earth into seconds: 8 minutes x 60 seconds/minute = 480 seconds. 
Since light takes over 4 hours to reach Neptune, we need to convert 4 hours into seconds: 4 hours x 60 minutes/hour x 60 seconds/minute = 14,400 seconds. 
Now, we can use the equation: 
distance = speed x time 
For Earth, the distance is:
distance = 299,792,458 m/s x 480 s = 143,999,027,840 meters
For Neptune, the distance is:
distance = 299,792,458 m/s x 14,400 s = 4,308,516,246,272 meters
Now, we can calculate the distance between the sun and Neptune by subtracting the distance to the Earth from the distance to Neptune:
distance = 4,308,516,246,272 m - 143,999,027,840 m = 4,164,517,218,432 meters
To convert this distance into astronomical units (AU), we need to divide by the distance from the Earth to the sun, which is about 150 million kilometers (or 150,000,000,000 meters):
distance = 4,164,517,218,432 m / 150,000,000,000 m = 27.8 AU
Therefore, the answer is B) 30 AU, which is the closest choice.

If Light Takes 8 Minutes to Travel from the Sun