DP Physics (last assessment 2024)
Question 18M.3.SL.TZ1.b
Date | May 2018 | Marks available | [Maximum mark: 2] | Reference code | 18M.3.SL.TZ1.b |
Level | SL | Paper | 3 | Time zone | TZ1 |
Command term | Estimate | Question number | b | Adapted from | N/A |
b.
[Maximum mark: 2]
18M.3.SL.TZ1.b
The Hubble constant is accepted to be 70 km s–1 Mpc–1. This value of the Hubble constant gives an age for the universe of 14.0 billion years.
The accepted value of the Hubble constant has changed over the past decades.
The redshift of a galaxy is measured to be z = 0.19.
Estimate, in Mpc, the distance between the galaxy and the Earth.
[2]
Markscheme
v = «zc = 0.19 × 3 × 108 =» 5.7 × 107 «ms–1»
d = «» = 810Mpc OR 8.1× 108 pc
Correct units must be present for MP2 to be awarded.
Award [2] for BCA.
[2 marks]
