拿一把已调好音的三弦或小提琴来,用不同的力度拨动琴弦,会发现:用力小时琴弦振动的幅度就小,发出的声音亦小;用力大时琴弦振动的幅度就大,发出的声音也就大。这是因为,声音的大小是由物体振动时偏离平衡位置的幅度所决定的。物理学把振动物体在平衡位置两边离开平衡位置的最大位移,称为振动的振幅。振动体振幅大时、声波的振幅也就大,媒质(如空气)因受声波干扰在压力上所产生的 Take a well-tuned soprano or violin, with different efforts to dial the strings, you will find: forced hours the amplitude of vibration of the strings is small, the sound is also small; force when the amplitude of the string vibration Large, the voice is loud. This is because the size of the sound is determined by the magnitude of the deviation from the equilibrium position when the object vibrates. Physics to the vibration object in the equilibrium position on both sides away from the equilibrium position of the maximum displacement, known as the vibration amplitude. Vibration amplitude is large, the amplitude of the sound wave is large, the medium (such as air) due to the sound waves generated by the pressure