Level 1: Pendulum: Middle to End in 0.6 s. Middle to Halfway?
Halfway out on both sides.
A particle performs SHM of amplitude A and period 12 s. The time it takes to move directly from x = +A/2 to x = −A/2 is:
Measured from the centre, the particle reaches A/2 in one twelfth of a period, because sin ωt = 1/2 when ωt = π/6. Going from +A/2 to −A/2 means passing through the centre, covering that stretch twice.
It takes 2 s, only one sixth of the period, although the distance is a full amplitude. Sharing the time out by distance, which gives 3 s, ignores how fast the particle moves near the centre.
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