Mechanical vs. Electromagnetic Waves

Mechanical Waves

• Waves that require a material medium

• Examples include water, sound, and waves along a spring or rope

• These materials carry the energy of the wave

Electromagnetic Waves

• Waves that DO NOT require a medium for motion

• Examples include light waves, radio waves, and X-rays

• All electromagnetic waves travel through space at the speed of light

• Since these waves can’t be observed, we study mechanical waves

Electromagnetic Waves

Waves

Mechanical Waves

Transverse Waves

Longitudinal Waves

Surface Waves

Electromagnetic Waves

Transverse Waves

• Particles of medium vibrate perpendicular to the direction of the motion of the wave

• Examples include guitar strings, waves in piano strings

Longitudinal Wave

• Particles of medium to move parallel to the direction of the wave

• Examples include sound waves, waves through fluids, liquids, gases or plasma

Surface Waves

• Mixture of transverse and longitudinal waves

• Example: At the surface of the water, particles move parallel and perpendicular to the direction of the wave.

Earthworm Examination

• Grab an earthworm from the vermicompost. Study the movement and decide whether an earthworm moves by longitudinal, transverse, or surface waves...

Types of Waves

• Using materials around the classroom, set up a demonstration showing a:– Transverse Wave– Longitudinal Wave– Surface Wave