## Problems on Units Analysis

#### Unit Analysis and Converstion Between Units

The following problems involve converstions bettween units. You will encounter many problems in astronomy that involve unit converstions so it is good to practice them. Also, where ever that you see it necessary - or "nicer" - to use scientific notation please do so.

1. Your friend's car gets 30 miles to a gallon. What is this gas mileage in km/liter?

2. Kim and Andrew ran a 10 km race last May.

a. How far did they run in miles?
b. How far did they rn in light years?

3. It typically takes 4 years to finish an undergaduate degree. How long is this amount of time in seconds?

4. A desk is advertised as 2 feet by 3.5 feet by 2 feet. What are the dimensions in centimeters?

5. A plane is flying at an altitude of 30,000 feet above sea level. How high is it in kilometers?

6. A 60 Watt light bulb uses 60 joules of energy per second (reall the definition of watts). How many ergs does it use per second? How many calories does it use per second?

7. If you had a 1-liter bottle of water and you poured it into a cube shaped box that would fill the box perfectly, how long would one side of the box be in inches?

8. Bob can run the mile in 6 minutes. What is his speed in kM/s?

9. John has a ball that has a density of 3 kg/m3. What is the density in lbs/in3?