# The Earth takes 1 day to rotate once about its axis. What is the angular velocity of a point on the surface of the Earth?

## I did this question and calculated the Angular velocity to be B but the exam answer booklet says A. Could someone please explain?

$7.3 \times {10}^{-} 5 \setminus \text{rad/s}$
Every point on the earth's surface completes one circular orbit (centered at a point on the axis) in 1 day $= 24 \times 60 \times 60 \setminus \text{s}$, i.e 86400 s.
omega = (2 pi)/(86400\ "s") = 7.3times 10^-5 \ "rad/s"