DP Physics (last assessment 2024)
Question 21M.2.SL.TZ1.2a.i
| Date | May 2021 | Marks available | [Maximum mark: 2] | Reference code | 21M.2.SL.TZ1.2a.i |
| Level | SL | Paper | 2 | Time zone | TZ1 |
| Command term | Explain | Question number | a.i | Adapted from | N/A |
a.i.
[Maximum mark: 2]
21M.2.SL.TZ1.2a.i
A planet is in a circular orbit around a star. The speed of the planet is constant.
(a.i)
Explain why a centripetal force is needed for the planet to be in a circular orbit.
[2]
Markscheme
«circular motion» involves a changing velocity ✓
«Tangential velocity» is «always» perpendicular to centripetal force/acceleration ✓
there must be a force/acceleration towards centre/star ✓
without a centripetal force the planet will move in a straight line ✓
