| Date | November 2016 | Marks available | 2 | Reference code | 16N.3.SL.TZ0.17 |
| Level | Standard level | Paper | Paper 3 | Time zone | Time zone 0 |
| Command term | Identify | Question number | 17 | Adapted from | N/A |
Question
The peak wavelength of the cosmic microwave background (CMB) radiation spectrum corresponds to a temperature of 2.76 K.
Identify two other characteristics of the CMB radiation that are predicted from the Hot Big Bang theory.
[2]
a.
A spectral line in the hydrogen spectrum measured in the laboratory today has a wavelength of 21cm. Since the emission of the CMB radiation, the cosmic scale factor has changed by a factor of 1100. Determine the wavelength of the 21cm spectral line in the CMB radiation when it is observed today.
[1]
b.
Markscheme
isotropic/appears the same from every viewing angle
homogenous/same throughout the universe
black-body radiation
a.
23 100 «cm»
OR
231 «m»
b.
Examiners report
[N/A]
a.
[N/A]
b.
