DP Physics (last assessment 2024)

Test builder »

Question 17N.3.SL.TZ0.13a

Select a Test
Date November 2017 Marks available [Maximum mark: 1] Reference code 17N.3.SL.TZ0.13a
Level SL Paper 3 Time zone TZ0
Command term Outline Question number a Adapted from N/A
a.
[Maximum mark: 1]
17N.3.SL.TZ0.13a

The collision of two galaxies is being studied. The wavelength of a particular spectral line from the galaxy measured from Earth is 116.04 nm. The spectral line when measured from a source on Earth is 115.00 nm.

(a)

Outline one reason for the difference in wavelength.

[1]

Markscheme

galaxies are moving away

OR

space «between galaxies» is expanding

Do not accept just red-shift

Syllabus sections