How fast is the Earth spinning?

How fast is the planet spinning? In this lesson students use rates, arc length, and trigonometry to determine the speed at which points on the Equator, Tropic of Cancer, and Arctic Circle travel due to the Earth's rotation. Think the Earth spins at the same speed everywhere? Think again!

- Given arc length and central angle, determine circumference of the Earth
- Use the period of rotation (one rotation every 24 hours) to calculate the rotation speed in miles per hour
- Given latitudes (central angles), determine circumference of latitude circle and speed of a point on that latitude, both for specific latitudes and generally
- Explain why the farther you travel away from the Equator, the more slowly you travel due to Earth's rotation

- Globe (optional)