DP Physics (last assessment 2024)
Question 19N.2.HL.TZ0.10a
Date | November 2019 | Marks available | [Maximum mark: 2] | Reference code | 19N.2.HL.TZ0.10a |
Level | HL | Paper | 2 | Time zone | TZ0 |
Command term | Predict | Question number | a | Adapted from | N/A |
a.
[Maximum mark: 2]
19N.2.HL.TZ0.10a
The lens of an optical system is coated with a thin film of magnesium fluoride of thickness d. Monochromatic light of wavelength 656 nm in air is incident on the lens. The angle of incidence is θ. Two reflected rays, X and Y, are shown.
The following refractive indices are available.
Air = 1.00
Magnesium fluoride = 1.38
Lens = 1.58
(a)
Predict whether reflected ray X undergoes a phase change.
[2]
Markscheme
there is a phase change ✔
of OR as it is reflected off a medium of higher refractive index ✔
