How many radians are there in a circle?

A full circle encompasses an angular measurement that can be expressed in radians. A complete rotation around a circle corresponds to 360 degrees. To convert degrees to radians, we use the relationship that 180 degrees is equal to π radians. Therefore, a full 360-degree circle can be converted to radians by using the conversion factor:

360 degrees × (π radians / 180 degrees) = 2π radians.

This means that the total angular distance in a circle, measured in radians, is 2π. This understanding is fundamental in trigonometry and geometry, and the relationship facilitates calculations involving angular measurements in various mathematical contexts. So, when asked how many radians are in a circle, the correct answer reflects this established conversion.