The nearest star to our sun is Proxima Centauri, at a distance of...

Question

The nearest star to our sun is Proxima Centauri, at a distance of
4.3 light-years from the sun. A light-year is the distance that
light travels in one year (365 days). How far away, in km, is Proxima
Centauri from the sun?

Accepted Answer

Hey everyone in this example, we're given a distance in astronomical units between two planets. And we need to convert this distance into units of meters. So what we should recognize is that we're given information for the distance in astronomical units which we can abbreviate two au So we would begin our answer by using the 5.6 astronomical units and then we should recognize that according to the conversion factor they give us one astronomical unit is equal to 8.31 67 light minutes. So we're going to plug that conversion factor in. So we would have that one astronomical unit in the denominator and then 8.31 67 light minutes in the numerator. So this allows us to cancel out a us leaving us with light minutes and then from light minutes, we can go directly into minutes by recalling that in one minute We have seconds. And so this allows us to cancel out minutes with light minutes and from seconds we want to lastly recall our conversion factor where we go from one second and that is equivalent to three times 10 to the eighth power meters. So lastly we can cancel out seconds, leaving us with meters. And when we type everything into our calculator, we're going to get a value of 8.38 times 10 to the 11th power meters. Now we want to pay attention to sig figs and we should recognize that in 5.6. A use that Only consists of 266, which is the lowest amount here. So we can go ahead and round this to two Sig figs, and that would give us 8.4 times 10 to the 11th Power meters. And so this is actually going to complete this example as our final answer for the distance between Planet A. And Planet B. So I hope that everything we reviewed was clear. If you have any questions, please leave them down below, and I will see everyone in the next practice video.

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