2.5 - Longitudinal and Transverse Waves

What are longitudinal waves?

waves where the vibrations are parallel to the direction of wave travel

What are examples of longitudinal waves?

• sound waves

• ultrasound waves

• seismic P-waves

What do longitudinal waves show?

areas of compression and rerefraction

What are compressions?

regions of high pressure due to particles being close together

What are rarefactions?

regions of low presure due to particles being spread further apart

How are longitudinal waves often demonstrated?

by pushing and pulling a stretched slinky spring

How does energy work in longitudinal waves?

the compressions move from left to right and energy is transferred from left to right, however, none of the particles are transported along a longitudinal wave, instead, they move backwards and forwards between compressions as the wave is transmitted through the medium

What are transverse waves?

the vibrations are at right angles to the direction of wave travel (perpendicular)

What are examples of transverse waves?

• ripples on the surface of water

• vibrations in a guitar string

• a Mexican wave in a sports stadium

• electromagnetic waves

• seismic S-waves

How are transverse waves often demonstrated?

moving a rope rapidly up and down

How does energy work in transverse waves?

the wave moves up and down, producing peaks and troughs, so energy is transferred from left to right, however, none of the particles are transported along a transverse wave and the particles move up and down as the wave is transmitted through the medium