Question

Derek is watching a thunderstorm. He hears the thunder 4.7 s after seeing a flash of lightning. How far away was the lightning?

Answer 1

Answer:

1.0014 Miles

Step-by-step explanation:

The light travels at 186,291 miles per second (~300,000 km/s), and speed of sound in dry air is equal to 0.21 - 0.22 miles per second (0.33-0.35 km/s), as it varies with the temperature. We can notice the lightning almost immediately even though the storm is far from us, but the thunder needs around 5 seconds to travel one mile and approximately 3 seconds to travel one kilometer. Thanks to this seven orders of magnitude difference in sound and light propagation, we can easily estimate the storm distance