DP Physics (last assessment 2024)
Question 19M.3.SL.TZ2.12a
| Date | May 2019 | Marks available | [Maximum mark: 2] | Reference code | 19M.3.SL.TZ2.12a |
| Level | SL | Paper | 3 | Time zone | TZ2 |
| Command term | Outline | Question number | a | Adapted from | N/A |
a.
[Maximum mark: 2]
19M.3.SL.TZ2.12a
(a)
Outline the differences between step-index and graded-index optic fibres.
[2]
Markscheme
refractive index of step index fibre is constant ✔
refractive index of graded index fibre decreases with distance from axis/centre ✔
graded index fibres have less dispersion ✔
step index fibre: path of rays is in a zig-zag manner ✔
graded index fibre: path of rays is in curved path ✔
For MP2 do not accept vague statements such as “index increases/varies with distance from centre”.
Examiners report
The differences between step index fibres and graded index fibres seem well-known.
