| Date | May 2015 | Marks available | 2 | Reference code | 15M.3.HL.TZ2.17 |
| Level | Higher level | Paper | Paper 3 | Time zone | Time zone 2 |
| Command term | Explain | Question number | 17 | Adapted from | N/A |
Question
This question is about gravitation.
Planets move in orbits around the Sun. Explain this observation according to
Newton’s universal law of gravitation.
Einstein’s theory of general relativity.
Markscheme
there is a force of attraction between (the mass of) the Sun and (the mass of) the planet;
which acts as a central/centripetal force for the planet;
(mass of the) Sun curves/warps spacetime around it;
planets move in paths of shortest length/geodesic (in this curved/warped spacetime);
Examiners report
Rather surprisingly candidates could explain the warping of spacetime and the shortest path followed by a planet but could not explain gravitational force providing centripetal motion.
Rather surprisingly candidates could explain the warping of spacetime and the shortest path followed by a planet but could not explain gravitational force providing centripetal motion.
