波與粒子 波的類型 機械波 電磁波 物質波:matter governed by Newton’s laws, exist only within a material medium (介質) 電磁波 governed by Maxwell’s laws, require no material medium to exist all travel at c = 299,792,458m/s 物質波:matter
橫波(Transverse Wave) Transversal wave displacement ⊥wave (橫波)
縱波(Longitudinal Wave) displacement ∥wave (縱波)
波長與頻率 一維波函數具有兩個變數:
常見之波動參數 振幅(amplitude) 相位(phase) 波長(wavelength) 角波數(angular wave number) 週期(period) 角頻率(angular frequency) 頻率(frequency)
波長(λ)與角波數(k) Why picking the sine wave? Need a videotape to show it in real time. Wavelength and angular wave number – wavelength (λ): Angular wave number(k):
週期(T)與角頻率 (ω) Period(T), angular frequency(w), and frequency(f)
行進波的波速 Traveling Wave The wave speed
A left-going wave
橫向速率與加速度
能量傳遞率
能量傳遞率–II 1/2
反射(Reflection)
折射(Refraction)
干涉(Interference)
波的重疊原理 The Principle of Superposition for Waves Fourier Analysis
波的干涉 合成波
完全建設性與完全破壞性(干涉) Fully constructive and fully destructive interference
繞射(Diffraction)
同相(in phase)與異相(out of phase) (exactly in phase/out of phase)
駐波 節點/反節點 node/antinode
在邊界反射之相位變化
駐波與共振 A string of length L n: harmonic number