DP Physics (first assessment 2025)
Question 20N.2.SL.TZ0.1a(ii)
| Date | November 2020 | Marks available | [Maximum mark: 2] | Reference code | 20N.2.SL.TZ0.1a(ii) |
| Level | SL | Paper | 2 | Time zone | TZ0 |
| Command term | Outline | Question number | a(ii) | Adapted from | N/A |
a(ii).
[Maximum mark: 2]
20N.2.SL.TZ0.1a(ii)
(a(ii))
Outline, by reference to Newton’s third law, how the upward lift force on the aircraft is achieved.
[2]
Markscheme
Blades exert a downward force on the air ✓
air exerts an equal and opposite force on the blades «by Newton’s third law»
OR
air exerts a reaction force on the blades «by Newton’s third law» ✓
Downward direction required for MP1.
Examiners report
The question required candidates to apply Newton's third law to a specific situation. Candidates who had learned the 'action and reaction' version of Newton's third law generally did less well than those who had learned a version describing 'object A exerting a force on object B' etc. Some answers lacked detail of what was exerting the force and in which direction.
