The Gaia space observatory measures the stellar parallax angle of a newly catalogued red dwarf star to be 1.25×10−3 arcseconds1.25 \times 10^{-3}\text{ arcseconds}1.25×10−3 arcseconds.
What is the distance to this star in light-years (ly\text{ly}ly)?
(Use 1 pc=3.26 ly1\text{ pc} = 3.26\text{ ly}1 pc=3.26 ly)
2.5×102 ly2.5 \times 10^2\text{ ly}2.5×102 ly
8.0×102 ly8.0 \times 10^2\text{ ly}8.0×102 ly
2.6×103 ly2.6 \times 10^3\text{ ly}2.6×103 ly
4.1×10−3 ly4.1 \times 10^{-3}\text{ ly}4.1×10−3 ly
66 exam-style questions on OCR A A Level Physics Astrophysics and cosmology, covering Stars, Electromagnetic radiation from stars, and Cosmology. Each one has a worked solution and a mark scheme showing where the marks go.