DP Physics (last assessment 2024)
Question 21M.2.HL.TZ2.b
| Date | May 2021 | Marks available | [Maximum mark: 1] | Reference code | 21M.2.HL.TZ2.b |
| Level | HL | Paper | 2 | Time zone | TZ2 |
| Command term | Explain | Question number | b | Adapted from | N/A |
b.
[Maximum mark: 1]
21M.2.HL.TZ2.b
In an experiment to demonstrate the photoelectric effect, monochromatic electromagnetic radiation from source A is incident on the surfaces of metal P and metal Q. Observations of the emission of electrons from P and Q are made.
The experiment is then repeated with two other sources of electromagnetic radiation: B and C. The table gives the results for the experiment and the wavelengths of the radiation sources.
Explain why there is no effect on the table of results when the intensity of source B is doubled.
[1]
Markscheme
changing/doubling intensity «changes/doubles number of photons arriving but» does not change energy of photon ✓
