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Knowing the speed of light (3x10m/s), calculate how long a

light year is in meters! (using dimensional analysis)

1 Answer

12 votes

Answer:

9.5 x 10^15 meters per year

Step-by-step explanation:

So, you have:


(300,000,000)/(1) (meters)/(second)

We want the amount of meters light travels in one year. There are 3600 seconds in 1 hour, 24 hours in 1 day, and 365 days in a year. Using these conversion factors, we can set up some nice cancellations:


(300,000,000)/(1) (meters)/(second)(3600)/(1) (seconds)/(hour) (24)/(1) (hours)/(day) (365)/(1) (days)/(year)

Seconds will cancel, hours will cancel, days will cancel. We have meters per year:


300,000,000*3600*24*365(meters)/(year) =9.5x10^(15)(meters)/(year)

User Safran Ali
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