Exam-style question
Try this first
A particle of mass 3 kg has resultant force 15 N. Find the acceleration.
- A.5 m s^-2
- B.8
- C.2
- D.10
Model answer
What a good answer should say
- The correct answer is 5 m s^-2.
This answer is tied to the objective: R2 Understand and use Newton's second law for motion in a straight line, restricted to forces in two perpendicular directions or simple cases of forces given as two-dimensional vectors, and extend to situations where forces need to be resolved in two dimensions..
Explanation
Why this works
Use the explanation to connect the worked answer back to R2 Understand and use Newton's second law for motion in a straight line, restricted to forces in two perpendicular directions or simple cases of forces given as two-dimensional vectors, and extend to situations where forces need to be resolved in two dimensions..
The distractors change the result or the form of the answer. The canonical solution reaches 5 m s^-2, so 5 m s^-2 is the only option consistent with the working.
Maths method check
- Topic focus: Mechanics.
- Question style: practice.
- Reasoning demand: application.
- Check the operation, notation, units, and final answer form against the question before moving on.
Common mistake
No common mistake is linked to this question yet.