# what is the linear speed of Santa Fe around the earth's axis in mi/hr

#### 699427535

##### New member
Santa Fe is approximately 33.88 degrees north of the equator. Given that the earth's radius at the equator is 3960 mi and the earth spins around its axis completely in 24 hours, what is the linear speed of Santa Fe around the earth's axis in mi/hr?

I don't know where to start! Thank you so much!

#### MarkFL

Consider the following diagram showing a cross-section of the Earth cut with a plane containing the axis of rotation. the vertex of the right triangle containg the angle $$\theta$$ is at the center of the Earth. The value $$a$$ is the radius of the circular path of Sante Fe as the Earth rotates.
Can you find a way to relate the radius of the Earth $$r_E$$, the latitude $$\theta=33.88^{\circ}$$ and $$a$$?