# An arc of 1 degree on earth's surface is equal to how many kilometers?

##### 1 Answer

At the equator,

#### Explanation:

The equatorial radius of the Earth is 6378.1 km.

The difference is 21.3 km. The polar radius is 6366.8 km.

At latitude

nearly.

An arc of 1 radian = the radial distance of the the latitude circle, from

the center.of the Earth.

So, the arc length

At the equator,

At Baltimore,

At the poles,

Note that this arc is along a great circle. If the arc arc is drawn by

traversing along a small circle, the length is less. If this small circle is

the latitude circle, apply a factor cos (latitude).