Physics A-Level
Relative motion
What Relative motion means in Physics A-Level, as defined for OCR.
Definition of Relative motion
Check what you remember
Read the wording for your board, then hide it and explain Relative motion in your own words. Rough notes are fine. This is a self-check, with no mark or grade.
Reference: OCR
Movement of a source of electromagnetic radiation relative to an observer, with the relative speed taken along the line of sight.
Topics that use Relative motion
- Cosmology (OCR A-Level)
Related terms
- Age of the universe
- Astronomical distance units
- Baseline
- Big Bang nucleosynthesis
- Big Bang theory
- Cosmic microwave background
- Cosmic microwave background radiation
- Cosmological redshift
Using Relative motion in the exam
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