Posts tagged fahrenheit
Ugh, I wanted to update more but got really busy/lazy/tired/sleepy/hungry/excited/etc/etc. I think eventually I’ll fill in the gaps but for now there’s a rather large blank in my vacation log.
Currently in Taipei waiting for the transit flight, 30 minutes to go followed by the 11+ hours flight home to LA.
Temperature Conversion Shortcut
EVA Air’s planes have an entertainment system that can cycle through various flight information. Basically a slide show that displays air speed, outside temperature, destination time/temperature, remaining flight time, etc. They cycle the same information in two languages and using two units, SI and English. Since I didn’t have much to do during the flight I occasionally glance up to see the flight info but sometimes temperatures are being displayed in Celsius so I have to convert it to Fahrenheit.
Remember the formula from your classes? F = (1.8 * C) + 32
Doing that a couple times is a bit tiring with the decimal multiplication so here’s a quick way to convert Celsius to Fahrenheit that I thought of in the plane:
- Take Celsius value and double it
- Subtract 10% of the doubled value
- Add 32
It’s quite simple now… say you’re converting 20C. Take 20, double it (40), subtract 10% (40-4 = 36), and finally add 32 (36+32=68). How about 17C? Doubling yields 34, subtract 3.4 = 30.6, add 32 = 62.6 F.
Aside from the regular shortcuts of 0C = 32F and -40C=-40F, this method works well for positive Celsius values. For negative values, there needs to be an additional step:
- Take absolute Celsius value and double it
- Subtract 10% of doubled value
- Subtract that value from 32
Example of converting -20C to Fahrenheit:
- Take absolute value and double it: Basically chop off the negative and double the number to get 40
- Subtract 10% of doubled value: 40-4 = 36
- Subtract value from 32: 32-36 = -4F
Maybe there are other ways to do it and I still haven’t found an easy way to go the other way around (F->C) but I think this will come in handy in the future