Question 22M.2.HL.TZ1.a
| Date | May 2022 | Marks available | [Maximum mark: 2] | Reference code | 22M.2.HL.TZ1.a |
| Level | HL | Paper | 2 | Time zone | TZ1 |
| Command term | Outline | Question number | a | Adapted from | N/A |
A mass–spring system oscillates horizontally on a frictionless surface. The mass has an acceleration when its displacement from its equilibrium position is .
The variation of with is modelled in two different ways, A and B, by the graphs shown.
Outline two reasons why both models predict that the motion is simple harmonic when is small.
[2]
For both models:
displacement is ∝ to acceleration/force «because graph is straight and through origin» ✓
displacement and acceleration / force in opposite directions «because gradient is negative»
OR
acceleration/«restoring» force is always directed to equilibrium ✓
This item was essentially encouraging candidates to connect concepts about simple harmonic motion to a physical situation described by a graph. The marks were awarded for discussing the physical motion (such as "the acceleration is in the opposite direction of the displacement") and not just for describing the graph itself (such as "the slope of the graph is negative"). Most candidates were successful in recognizing that the acceleration was proportional to displacement for the first marking point, but many simply described the graph for the second marking point.
