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A2 Daily A Level Physics question

2026-06-26 OCR A Simple Harmonic Motion (M5) OCR A (H556) Module 5.1.1 Simple harmonic motion: displacement, velocity, acceleration and phase OCR A (H556) Module 5.1.1 Simple harmonic motion: energy interchange between kinetic and potential

A glider on a low-friction air track is attached to a horizontal spring and oscillates with small amplitude. When the glider is at its maximum displacement to the right, which statement must be true?

  1. A Its velocity is maximum; acceleration is zero; kinetic energy is maximum; elastic potential energy is minimum.
  2. B Its velocity is zero; acceleration is maximum towards the left; kinetic energy is at a minimum; elastic potential energy is at a maximum. (correct)
  3. C Its velocity is maximum to the left; acceleration is maximum to the right; kinetic energy is maximum; elastic potential energy is minimum.
  4. D Its velocity is zero; acceleration is zero; both kinetic and elastic potential energies are maximum.

Answer

The correct answer is B.

Correct: B — Its velocity is zero; acceleration is maximum towards the left; kinetic energy is at a minimum; elastic potential energy is at a maximum. A confuses the turning point with the centre: at maximum displacement speed is zero, acceleration is not zero, and elastic potential energy is largest, not smallest. B matches SHM at an extreme: turning point has zero speed, restoring acceleration largest toward equilibrium, KE minimum and PE maximum. C reverses directions and places maximum speed at the turning point instead of at the centre. D incorrectly sets acceleration to zero at the turning point and claims both energies are maximum, which cannot happen in SHM.