简谐振动运动规律x=Acos(ωt+a) (1)v=-Aωsin(ωt+a) (2)Ek=mv^2/2 ,Ep=kx^2当 Ek=Ep mv^2/2 =kx^2/2代入(1)(2)式m(-Aωsin(ωt+a))^2=k(Acos(ωt+a))整理并代入ω^2=k/m ,有tan(ωt+a)=1则相位角(ωt+a)=π/4±π时Ek=Ep。
