Question 22M.2.SL.TZ1.e
| Date | May 2022 | Marks available | [Maximum mark: 3] | Reference code | 22M.2.SL.TZ1.e |
| Level | SL | Paper | 2 | Time zone | TZ1 |
| Command term | Explain | Question number | e | Adapted from | N/A |
The student then makes the ramp horizontal and applies a constant horizontal force to the box. The force is just large enough to start the box moving. The force continues to be applied after the box begins to move.
Explain, with reference to the frictional force acting, why the box accelerates once it has started to move.
[3]
static coefficient of friction > dynamic/kinetic coefficient of friction / μs > μk ✓
«therefore» force of dynamic/kinetic friction will be less than the force of static friction ✓
there will be a net / unbalanced forward force once in motion «which results in acceleration»
OR
reference to net F = ma ✓
This was an "explain" question, so examiners were looking for a clear line of discussion starting with a comparison of the coefficients of friction, leading to a comparison of the relative magnitudes of the forces of friction and ultimately the rise of a net force leading to an acceleration. Many candidates recognized that this was a question about the comparison between static and kinetic/dynamic friction but did not clearly specify which they were referring to in their responses. Some candidates clearly did not read the stem carefully as they referred to the mass being on an incline.
