3.1.3

Longitudinal & Transverse Waves

Test yourself

Transverse Waves

Here are some examples of transverse waves:

Moving springs

• Waving/moving the coils of a spring will make the coils move up and down as the wave passes.
• They then return to their original position after the wave has passed.
• This shows that a wave moves without transferring matter because the spring coils do not travel along with the wave.

Mexican wave

• A “Mexican wave” at a sports event is an example of a transverse wave.
• The wave spreads around the stadium as the people stand up and sit down one after the other (at right angles to the direction of the people’s motion).

Corks bobbing

• A cork bobbing on the water shows how a transverse wave works.

Longitudinal Waves

Here are some example of longitudinal waves:

Pulling & pushing springs

• Pushing the spring in and out (compressing and extending), longitudinal waves are created.
• The coils and the wave move along the same line.

Sound waves

• Sound waves are longitudinal waves.

P-waves

• P-waves are pressure waves created during earthquakes.
• They are longitudinal waves.

Electromagnetic Waves

All electromagnetic waves are transverse and travel at the same speed.

Transverse

• All electromagnetic waves are transverse waves.
• The electric and magnetic fields oscillate perpendicular to the direction of energy propagation.
• All electromagnetic waves travel at the speed of light, c, in a vacuum.
• The speed of light is c = 3 x 108 m/s.