Light from the sun reaches Earth in 8.3 min. The velocity of light is 3.00 108 m/s. Given this info, how would you determine how far the Earth is from the sun?

Dec 26, 2015

$d = 1.49 \times {10}^{11} \text{m}$

Explanation:

Velocity is defined as the rate of travel, and can be found using the distance formula.

$\text{velocity" = "distance"/"time}$

Rearranging this formula we can solve for distance given velocity and time of travel.

$d = v t$

We are given velocity and time, and so can solve for distance, but if we plug in the values given;

$d = \left(3.00 \times {10}^{8} \text{m/s")(8.3"minutes}\right)$

We can see that the units do not match up. Since seconds are the SI unit for time, we will need to convert 8.3 minutes to seconds.

$t = \left(8.3 \text{minutes")(60 "seconds/minute")=(498 "s}\right)$

Now our units work out and we can solve for distance.

$d = \left(3.00 \times {10}^{8} \text{m/s")(498 "s}\right)$

$d = 1.49 \times {10}^{11} \text{m}$