2.4: Conversions with Time
- Page ID
- 142698
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You may use a calculator in this module as needed.
Converting Measurements of Time
You probably know all of the necessary conversions for time. When we get to units of time larger than weeks, however, we encounter problems because not all months have the same number of days, a year is not exactly \(52\) weeks, and the time it takes for the Earth to orbit the Sun is not exactly \(365\) days. Therefore, it doesn’t make sense to expect an exact answer to a question like “how many minutes are in one month?” We will have to use our best judgment in situations such as these.
\(1\) min = \(60\) sec
\(1\) hr = \(60\) min
\(1\) day (dy) = \(24\) hr
\(1\) week (wk) = \(7\) dy
\(1\) year (yr) = \(365\) dy
1. How many minutes is one standard \(365\)-day year?[1]
2. Have you been alive for \(1\) billion seconds? Is this even possible?
- Answer
-
1. \(525,600\) min
2. this is roughly \(31.7\) years, which is indeed possible
Converting Rates
Usain Bolt holds the world record time for the \(100\)-meter dash, \(9.58\) seconds.
3. What was his average speed in kilometers per hour?
4. What was his average speed in miles per hour?
- Answer
-
3. \(37.6\) km/hr
4. \(23.3\) mi/hr
The more information we know, the more things we can figure out.
An F-\(15\) fighter jet can reach a sustained top speed of roughly Mach \(2.3\); this is \(2.3\) times the speed of sound, which is \(770\) miles per hour.[2]
5. What is the jet’s top speed in miles per hour?
6. At this speed, how many miles would the jet travel in one minute?
The jet’s range at this speed before it runs out of fuel is around \(600\) miles.
7. If the jet flies \(600\) miles at top speed, for how many minutes will it fly?
The jet’s maximum fuel capacity is \(3,475\) gallons of fuel.
8. If the jet flies \(600\) miles and burns \(3,475\) gallons of fuel, find the jet’s fuel efficiency, in miles per gallon.
9. Rewrite the jet’s fuel efficiency, in gallons per mile.
10. How many gallons of fuel does the jet consume in one minute?
- Answer
-
5. \(1,770\) mi/hr
6. \(29.5\) mi in \(1\) min
7. \(20.3\) min
8. \(0.17\) mi/gal
9. \(5.8\) gal/mi
10. \(171\) gal in \(1\) min
- If you're familiar with the musical Rent, then you already know the answer. ↵
- My sources for the following set of questions are a combination of former students in the Air National Guard and people who sound like they know what they're talking about on the internet, particularly in this Quora discussion. ↵