Question

A prism with an apex angle of 30° is found empirically to have an n vs. λ relationship given by n=1+13,500,000λ2 where λ is measured in angstroms. At what angle of minimum deviation does 6000 Å light emerge? Answer to 3 significant figures.

13,500, 000

11.7°

None of the above.

11.6°

11.8°

11.9°

Answer 1

The minimum angle of deviation is calculate by using formula delta_m = A(n - 1) But n = 1 + 13500000/lambda^2 delta_m = A[1 + 13500000/lambda^2 - 1] delta_m = A [13500000/lambda^2] A = Apex angle = 30 degrees lambda = 6000 A degrees delta_m = 30 degrees [13500000/(6000)^2] delta_m = 11.3 Answer is none of the above