12 second for one cycle, and 2 seconds is 2/ 12 cycle =2/ 12*2π=π/3.

π/6+π/3=π/2

Point B is at π/2, and the coordinate is (0, 1).

The polar angle of point A is π/6, and the coordinates of point A can also be written as (cosπ/6, sinπ/6).

The coordinates of any point in the unit circle can be written as (cos φ, sin φ), where φ is the polar angle of any point in the unit circle.

φ changes from point A at the rate of 12 second. If the time is t, φ= 2π/ 12 * t+π/6 =π/6t+π/6.