DP Physics (last assessment 2024)
Question 17N.2.SL.TZ0.4a.ii
Date | November 2017 | Marks available | [Maximum mark: 3] | Reference code | 17N.2.SL.TZ0.4a.ii |
Level | SL | Paper | 2 | Time zone | TZ0 |
Command term | Show that | Question number | a.ii | Adapted from | N/A |
a.ii.
[Maximum mark: 3]
17N.2.SL.TZ0.4a.ii
A large cube is formed from ice. A light ray is incident from a vacuum at an angle of 46˚ to the normal on one surface of the cube. The light ray is parallel to the plane of one of the sides of the cube. The angle of refraction inside the cube is 33˚.
(a.ii)
Show that no light emerges from side AB.
[3]
Markscheme
light strikes AB at an angle of 57°
critical angle is «sin–1 =» 50.1°
49.2° from unrounded value
angle of incidence is greater than critical angle so total internal reflection
OR
light strikes AB at an angle of 57°
calculation showing sin of “refracted angle” = 1.1
statement that since 1.1>1 the angle does not exist and the light does not emerge
[Max 3 marks]
