How long would light take to travel 1.20 × 10^6 meters, given the speed of light as 3.00 × 10^8 meters per second?

How long would light take to travel 1.20 × 10^6 meters, given the speed of light as 3.00 × 10^8 meters per second?

• A. 0.04 s
• B. 0.0004 s
• C. 0.004 s
• D. 0.04 ms

Answer: (C)

Time is found by dividing distance by speed. With a distance of 1.20 × 10^6 meters and the speed of light as 3.00 × 10^8 meters per second, you get time = (1.20 × 10^6) / (3.00 × 10^8) seconds. That simplifies to (1.20/3.00) × 10^(6−8) = 0.40 × 10^−2 = 4.0 × 10^−3 s, which is 0.004 seconds. So light would take 0.004 seconds to travel that distance.

Time is found by dividing distance by speed. With a distance of 1.20 × 10^6 meters and the speed of light as 3.00 × 10^8 meters per second, you get time = (1.20 × 10^6) / (3.00 × 10^8) seconds. That simplifies to (1.20/3.00) × 10^(6−8) = 0.40 × 10^−2 = 4.0 × 10^−3 s, which is 0.004 seconds. So light would take 0.004 seconds to travel that distance.