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Oscillations

Equation of motion


Solutions were already suggested, in the form

u(t) = A sin(ωt)


Indeed, the second order time derivative of such expression gives

du/dt = ωA cos(ωt)    and    d2u/dt2 = -ω2A sin(ωt) = -ω2 u(t)


This solution relates the angular frequency ω with the elasticity constant Cel and the mass m of the object:

ω2 = Cel/m      or      ω = √(Cel/m)


So, when we know the mass m of the object and the elasticity constant Cel of the spring, then we can predict the period T=2π/ω or the frequency f=ω/2π of the oscillations of the mass-spring system.



Harmonic motion