Normal ShiftHardQuestion 20223
Question
An object in glass (n = 1.5) appears shifted when viewed from air. Normal shift (how much it appears to move toward the surface) is:
- At(1 − 1/n) = t/3Correct
- Bt(n − 1) = t/2
- Ct/n
- Dt(n + 1)
Correct answer
t(1 − 1/n) = t/3
Explanation
Apparent depth = real depth/n. Object appears at depth d/n instead of d. Shift = d − d/n = d(1 − 1/n) = t/3 for n = 1.5. The object appears closer by t/3.