Nikon AF-S 35mm DX Nikkor F/1.8G on a D7000?

What would be the actual focal length of the lens, since the camera is an AFS-C.
How do you calculate this difference?

The focal length is still the same, only the field of view changes. To calculate, just multiply by 1.5 for Nikon, Sony and Pentax they all use Sony Exmor sensors. For Canon, it's 1.6

Sound labs is correct! 1.5x for Nikon and 1.6x for canon!
To be exact it would be 52.5mm.

35mm.

A 35mm lens is a 35mm lens, regardless of whether it is used on a Dx or Fx camera body.

What does change is the cropped Dx camera takes a smaller image, so when enlarged to the same size as the Fx camera photo, it looks like it was taken with a lens having a longer focal length.

But too much emphasis has been put on this characteristic. Just remember that when compared to Fx cameras, Dx cameras "crop" the photo, just as you would in photoshop. Of course this is not 100% accurate, but conceptually it gives you a good idea of what is going on.

Still 35mm.

?!

Focal length does not change. Only angle of view does. The 35mm on an APS-C camera will have an angle of view almost similar to a 50mm on a full-frame or 35mm film camera.

http://keerok-photography.blogspot.com/2011/05/lenses-so-many-of-them-there-is-no-best.html#cropfactor