DP Physics (last assessment 2024)
Question 19N.3.HL.TZ0.a(i)
| Date | November 2019 | Marks available | [Maximum mark: 2] | Reference code | 19N.3.HL.TZ0.a(i) |
| Level | HL | Paper | 3 | Time zone | TZ0 |
| Command term | Outline | Question number | a(i) | Adapted from | N/A |
a(i).
[Maximum mark: 2]
19N.3.HL.TZ0.a(i)
Outline how the light spectra of distant galaxies are used to confirm hypotheses about the expansion of the universe.
[2]
Markscheme
spectra of galaxies are redshifted «compared to spectra on Earth» ✔
redshift/longer wavelength implies galaxies recede/ move away from us
OR
redshift is interpreted as cosmological expansion of space ✔
«hence universe expands»
NOTE: Universe expansion is given, so no mark for repeating this.
Do not accept answers based on CMB radiation.
