DP Physics (last assessment 2024)
Question 20N.2.HL.TZ0.9a
| Date | November 2020 | Marks available | [Maximum mark: 3] | Reference code | 20N.2.HL.TZ0.9a |
| Level | HL | Paper | 2 | Time zone | TZ0 |
| Command term | Explain | Question number | a | Adapted from | N/A |
a.
[Maximum mark: 3]
20N.2.HL.TZ0.9a
The diagram shows an alternating current generator with a rectangular coil rotating at a constant frequency in a uniform magnetic field.
(a)
Explain, by reference to Faraday’s law of induction, how an electromotive force (emf) is induced in the coil.
[3]
Markscheme
there is a magnetic flux «linkage» in the coil / coil cuts magnetic field ✓
this flux «linkage» changes as the angle varies/coil rotates ✓
«Faraday’s law» connects induced emf with rate of change of flux «linkage» with time ✓
Do not award MP2 or 3 for answers that don’t discuss flux.
Examiners report
This question was well answered with the majority discussing changes in flux rather than wires cutting field lines, which was good to see.
