Modes of Propagation/Waves (1)

Question 1

Longitudinal (Compression)

Answer 1

Particle motion parallel to wave direction.

• Only wave that can Propagate Liquids
• Highest Velocity wave

Question 2

Transverse (Shear)

Answer 2

Created by refracting a longitudinal wave at the entry surface.

• Similar to vibration of a rope.
• Needs rigidity

Question 3

Surface (Rayleigh)

Answer 3

Particle Motion is elliptical.

• Only travel 1 Wavelength below surface
• Will reflect if from surface discontinuities

Question 4

Plate (Lamb)

Answer 4

Vibrate the whole plate. 
- Symmetrical (Stressor, Dilatational)
- Asymmetrical (Bending)
Impacting Factors:
- Material Thickness
- Type of material
- Wave Frequency
- Angle of Incidence
- Mode of Wave