Page 46 - Science Course 3 (Book 2)

Mo10-L1a: What are Waves and How are They Made?

Key Concept A wave in which the disturbance is perpendicular to
the direction the wave travels is called a transverse
What are Waves and How are They Made? wave.

How are waves produced? High points on the wave are called crests, and low
points are called troughs.

Crest

Trough

Some wave move particles of a medium up and A wave that makes the particles in a medium move
down or side to side, perpendicular to the direction back and forth along the direction the wave travels is
the wave travels. called a longitudinal wave.

Other waves move particles of the medium forward
then backward in the same direction, or parallel, to
the motion of the wave.

Longitudinal waves are mechanical waves because
Three types of wave motion are transverse, this type of motion can occur only when energy
longitudinal, or a combination of both. passes from particle to particle.

TYPE OF WAVES

Wave Motion Mechanical Electromagnetic
Wave
Waves

Transverse
Perpendicular to the direction the wave travels. Flag waving in breeze Light waves

Longitudinal
Parallel to the direction the wave travels. Sound waves

Combination
both transverse and longitudinal Water waves

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