Wave Equation and Types of Waves
A progressive wave is described by y = A sin(wt - kx), with v = f λ = w/k.
What is Wave Equation and Types of Waves?
A progressive wave is described by y = A sin(wt - kx), with v = f λ = w/k.
Key formula / rule: v = f λ; k = 2 π/λ; w = 2 π f.
Key points
- Apply the wave relation to compute speed, frequency and wavelength.
- Compare transverse and longitudinal waves.
Common exam trap
Assuming the particle speed equals the wave speed.
Definitions
- Term
Wave Equation and Types of Waves
- Meaning
A progressive wave is described by y = A sin(wt - kx), with v = f λ = w/k.
- Term
Wave Equation and Types of Waves — explanation
- Meaning
Waves transport energy without net transport of matter. Transverse waves need a medium that supports shear, so they do not travel through gases, while longitudinal waves do.
Learning objectives
Apply the wave relation to compute speed, frequency and wavelength.
Compare transverse and longitudinal waves.
Formulae
- Key point
v = f λ; k = 2 π/λ; w = 2 π f.
- Key point
Speed on a string: v = √(T/μ).
- Key point
Sound in air is longitudinal; light is transverse and needs no medium.
Prerequisites
PHY-U4-SHM-T1-S1-C1
Common mistakes
Assuming the particle speed equals the wave speed.
Expecting the frequency to change when a wave enters a new medium; the wavelength changes instead.
Keywords
Equation
Types
Waves
Practice preview
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