Radians and Degrees of the Unit Circle

Front

What is a radian?

Back

A radian is a unit of angular measure defined as the angle subtended at the center of a circle by an arc equal in length to the radius of the circle.

Front

How many radians are in a full circle?

Back

There are 2π radians in a full circle.

Front

Convert 180 degrees to radians.

Back

180 degrees is equal to π radians.

Front

Convert 90 degrees to radians.

Back

90 degrees is equal to π/2 radians.

Front

What is the relationship between degrees and radians?

Back

Degrees can be converted to radians by multiplying by π/180.

Front

What is the unit circle?

Back

The unit circle is a circle with a radius of 1 centered at the origin of a coordinate plane.

Front

What are the coordinates of the point at 0 radians on the unit circle?

Back

The coordinates are (1, 0).

Front

What are the coordinates of the point at π/2 radians on the unit circle?

Back

The coordinates are (0, 1).

Front

What are the coordinates of the point at π radians on the unit circle?

Back

The coordinates are (-1, 0).

Front

What are the coordinates of the point at 3π/2 radians on the unit circle?

Back

The coordinates are (0, -1).