In terms of field of view, or framing, APS-C is defined as a ratio to full frame. For Canon it's 1.6, for Nikon/Pentax/Sony it's 1.5. So, when looking at this:

X x 1.5 = Y

X is the focal length on the APS-C and Y is the focal length on the FF. So, we sub in and rearrange for:

X = 50 / 1.5
X = 33.3333

So, you'll get around the same field of view if the lens on APS-C is between 30 and 35mm. Now, if you're using the same lens, you'll have to use your feet. For APS-C, that means moving back and the distance will depend on the subject, but the perspective will change.

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So, if the lens is the same...

As mentioned in both answers, the perspective will change as a result of changing position, so the essential answer is no, you can't when you're using the same lens. That leaves you with the last option I can think of: panorama. Several shots, 4 minimum I would think (2 top, and 2 bottom) would allow you to construct an image with the same perspective (or so very close that the difference is very difficult to detect) and same field of view. The drawbacks are obvious and include multiple images, must be a stationary subject, and more. Technically, however, it could be done given a suitable subject.