Particle Velocity and Wave Velocity Relation (v_particle = -v_wave × (∂y/∂x))

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v_particle = -v_wave × (∂y/∂x)

What each symbol means

SymbolWhat it stands for
v_pParticle (transverse) velocity (m/s)
v_waveWave propagation velocity (m/s)
∂y/∂xSlope of wave at that point

When to use this

Relates transverse particle velocity to slope of wave displacement. For y = a sin(kx - ωt): v_p = -aω cos(kx - ωt) and ∂y/∂x = ak cos(kx - ωt). Maximum particle velocity v_p_max = aω. Particle velocity and wave velocity are perpendicular for transverse waves.