Question

The speed of light is 3 x 10^8 meters/second. If the sun is 1.5 X 10^11 meters from earth, how many seconds does it take the sunlight to reach the Earth? (Time = Distance/Speed).

Answer 1

Time = 500 seconds or 8.333 minutes

Explanation:

Time = Distance/Speed

Speed of light = 3 x 10^8 meters/second

Distance=1.5 X 10^11 meters

Time = 1.5 X 10^11 meters/3 x 10^8 meters/second

We solve using the scientific notation. When 8 is taken to the top it is subtracted from 11 ( the base 10 is the same -- laws of exponents)

Dividing 1.5 by 3 gives 0.5 .

Time = 1.5 X 10^(11- 8) meters/3 meters/second

Time = 0.5 X 10^3 seconds

Time = 500 seconds

Dividng seconds with 60 will give minutes

Time= 500/60 = 8.333 minutes