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AS Daily A Level Physics question

2026-02-18 OCR A Foundations of Physics (M2) OCR AS Physics A (H156) Module 2.1.1 Physical quantities and units (SI) OCR AS Physics A (H156) Module 2.1.2 Scalars and vectors (displacement vs distance)

A student walks 300 m east along a straight corridor, then 400 m west along the same corridor. Which statement must be true about the student’s displacement from the starting point?

  1. A The magnitude of the displacement is 700 m.
  2. B The displacement is 100 m west. (correct)
  3. C The displacement is 100 m east.
  4. D The displacement is 0 m.

Answer

The correct answer is B.

Correct: B — The displacement is 100 m west. A confuses displacement with distance; 700 m is the total distance, not the vector change. B is correct because the net change is 400 m − 300 m = 100 m towards the west. C has the right magnitude but the wrong direction. D would only be true if the student returned to the start (equal distances each way), which they did not.