A radian is a unit of angle, equal to an angle at the center of a circle whose arc is equal in length to the radius. If I were to explain to a person that doesn't know anything about radians I would say to look at a circle and if you know the degrees of an angle in this circle then you can also find the radian. One radian is the same length as the radius. The radian is just a angle measure in the circle. Lets say the measure is 15 degrees which is usually one radian. Then you just have to change it to radians by multiplying the degrees by pi/180. :-).
When I explained the definition of a radian I basically said how it was related to the circle because the degrees of the circle can be changed to radians and vice versa. Also again the length of the radian is the same as a radius.
The formula for circumfrence is C=2pir, and the whole circle in radians is described as 2Pi Radians. Which is basically the same formula.
Radians can be changed to degrees and degrees can be changed to radians. The formula for randians to degrees is multiply the radian by 180/pi and the formula for degrees to radians is pi/180. I like degrees of course, because I think they're easier to work with. I'm guessing that radians is more mathmatically pure, it's more raw compared to degrees.
Here's some pictures for more help.
When I explained the definition of a radian I basically said how it was related to the circle because the degrees of the circle can be changed to radians and vice versa. Also again the length of the radian is the same as a radius.
The formula for circumfrence is C=2pir, and the whole circle in radians is described as 2Pi Radians. Which is basically the same formula.
Radians can be changed to degrees and degrees can be changed to radians. The formula for randians to degrees is multiply the radian by 180/pi and the formula for degrees to radians is pi/180. I like degrees of course, because I think they're easier to work with. I'm guessing that radians is more mathmatically pure, it's more raw compared to degrees.
Here's some pictures for more help.