Light travels at about 300 million meters per second, and it takes light 100,000 years to go from one end of our galaxy to the other. How many miles across is our galaxy? A) 100,000 m B) 300,000,000 m C) 9.3x10²⁰m D) 9.3x10²⁰km

Question

Quizplus · Accepted Answer

To calculate the distance across the galaxy in miles, first convert the time to seconds (100,000 years * 365.25 days/year * 24 hours/day * 3600 seconds/hour), then multiply by the speed of light (300,000,000 meters/second) to get the distance in meters, and finally convert meters to miles (1 meter = 0.000621371 miles). The correct calculation leads to a distance of about 5.878625 trillion miles, which is approximately 9.461x10^15 kilometers, or in the format given in the options, 9.3x10^21 meters, recognizing the scientific notation and unit conversion.

Light Travels at About 300 Million Meters Per Second, and It