Light Year Question: When Will We See It?

AI Thread Summary
If a star explodes 30 light years from Earth, it will take 30 years for the light from that explosion to reach us. This is based on the definition of a light year, which is the distance light travels in one year. The calculations confirm that light will take 30 years to cover the distance of 30 light years. The term "a" in the workbook likely refers to "annum," meaning year. Therefore, the answer to when we will see the explosion is 30 years from the event.
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Homework Statement


If a star explodes 30 light years from the Earth when will we be able to see it?


Homework Equations



one light year = 9.47 x 1012km
speed of light = 3.00 x 108m/s

The Attempt at a Solution


the answer in my workbook says 30a but idk what the value of a is
 
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The definition of light year tells us that light will take 30 years to travel that distance, so the answer is indeed 30 years.
 
a could be an abbreviation for annum (year) or anni (years).
 

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