The Optical Spy box is split into the top third and the bottom two thirds. So which line is longer, the diagonal splitting the top third A-B or the diagonal splitting the bottom two thirds B-C?

The Optical Spy box is split into the top third and the bottom two thirds. So which line is longer, the diagonal splitting the top third A-B or the diagonal splitting the bottom two thirds B-C?

They both look the same length to me, but there must be something wrong with that shadow.

So, if we were to assume that the box faces are rectangles where the shorter side is 1 unit, and the longer 3, then:

AB = √2 = 1.414213562

BC = √5 = 2.23606798

Which makes BC the longer as you would expect. But I guess that it would be dangerous to assume (or expect) that all is as I think it appears, and maybe the answer is AB = BC

I think this is the best answer that could be given. Well done Steve.

But those are the true lengths. We are viewing from an angle with perspectives. The shadow still doesn’t work for me.