Why Radians?
Ever wondered why there are 360 degrees?
Constellations make a circle throughout the year — ever see the Big Dipper upside down sometimes? (Never fear, it’ll be rightside-up in 6 months). Here’s a theory about how degrees came to pass:
- Humans noticed that constellations moved in a full circle every year
- Every day, they moved a tiny bit (†a degreeâ€)
- Since a year has about 360 days, a circle had 360 degrees
But, but… why not 365 degrees in a circle?
Cut ‘em some slack: they had sundials and didn’t know a year should have a convenient 365.242199 degrees like you do.
360 is close enough for government work. It fits nicely into the Babylonian base-60 number system, and divides well (by 2, 3, 4, 6, 10, 12, 15, 30, 45, 90… you get the idea).
According to Better Explained, degrees are subjective but radians are objective.
A degree is the amount I, an observer, need to tilt my head to see you, the mover. It’s a tad self-centered, don’t you think?
…
Much of physics (and life!) involves leaving your reference frame and seeing things from another’s viewpoint. Instead of wondering how far we tilted our heads, consider how far the other person moved.