Exam-style question
Try this first
A particle of mass 4 kg has resultant force 14 N. Find the acceleration.
- A.3.5 m s^-2
- B.5.5
- C.1.5
- D.7
Model answer
What a good answer should say
- The correct answer is 3.5 m s^-2.
This answer is tied to the objective: R4 Understand and use Newton's third law; use equilibrium of forces on a particle and motion in a straight line, restricted to forces in two perpendicular directions or simple two-dimensional vector cases; apply to smooth pulleys and connected particles; resolve forces in two dimensions; use equilibrium of a particle under coplanar forces..
Explanation
Why this works
Use the explanation to connect the worked answer back to R4 Understand and use Newton's third law; use equilibrium of forces on a particle and motion in a straight line, restricted to forces in two perpendicular directions or simple two-dimensional vector cases; apply to smooth pulleys and connected particles; resolve forces in two dimensions; use equilibrium of a particle under coplanar forces..
calculator check uses Newton's third law and equilibrium: identify the quantities, do the stated operation, and select 3.5 m s^-2 because it matches the verified final answer.
Maths method check
- Topic focus: Mechanics.
- Question style: practice.
- Reasoning demand: understanding.
- 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.