How Thick Is the Glass Plate Based on Visibility Circle?

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SUMMARY

The discussion centers on calculating the thickness of a glass plate with a refractive index of 1.5, given a visibility circle radius of 1 meter and a critical angle of 41.8º. The conclusion reached is that the glass plate must be 381 inches thick to achieve the specified visibility conditions. The conversation highlights that the problem was poorly formulated, as the wavelengths provided are irrelevant to the solution. It emphasizes the necessity of the observer being in fluid contact with the glass for total internal reflection to occur.

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Optics question-- please reply ASAP

A person stands against a thick plate of glass, n=1.5. everything on the other side of the glass plate is inside of a circle of radius = 1 meter.
wavelength air = 600 x 10 ^ -9 meters
wavelength of glass = 4 x 10 ^ -7 meters
Critical angle of glass plate = 41.8º

HOW THICK IS THE GLASS PLATE?
 
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This problem is pooly formulated and posted.

Glass doesn't have a wavelength, and how far is the person from the glass?

If my eyeball doesn't touch the glass then I will see all the way to infinity, not
just to a 1 meter radius. My eyeball would have to be in fluid contact with the
window in order for there to be a point of total internal reflection which is visible
to me.

That having been said, the glass plate would be 381 Inches thick.
 
I agree that the problem is not clearly stated. I interpret it this way: looking at the person's image from the other side of the glass, every point is only visible inside a circle of radius 1 meter. With this interpretation, the problem is solvable. (The wavelengths are irrelevant.)
 

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