[masrawy2009]

Solution NO.1

the platform goes down 2.20 cm and 1 cm up so it covers 0.6875 cycle downwards :

∵ Frequency = cycles / time
∴ 6.60 = 0.6875 / time
∴ time = 0.1

∵ Distance = 0.5 a X t^2
∴ acceleration ≈ 4 m/sec^2

اتمنى ان تكون اجابتى صحيحة وو اضحة

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