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### Course: Middle school physics - NGSS>Unit 4

Lesson 1: Wave properties

# Wave properties

Review your understanding of wave properties in this free article aligned to NGSS standards.

## Key points:

• A wave is a repeating disturbance that travels through matter or space transferring only energy.
• Below is a model of a wave.
• A wave’s crest is its highest point, and its trough is its lowest point.
• A wave’s amplitude is the maximum distance (positive or negative) a wave reaches from its rest position.
• Wavelength is the distance between the same spot on two sections of a wave.
• A wave’s frequency can be measured by how many crests (or how many troughs) pass a location in a certain amount of time.
• A wave with a larger frequency has more energy. If a wave’s frequency doubles, its energy also doubles.
• A wave’s energy is proportional to the square of its amplitude. So, if a wave’s amplitude doubles, its energy increases by four times, because ${2}^{2}=4$.

## Want to join the conversation?

• Is there a certain name for the starting point of a wave?
• is it the period?
• What ocean has waves with the higest frequency?
• not that type of wave bro
• why does the wave go up and down?
• Doesn't have to. Depends on how the energy is moving.
• What gives the wave energy
• A wave is one way of how energy travels, so the wave is energy itself. How the energy travels as a wave, such as its velocity, depends on the type of energy however. A pulse of electromagnetic energy, for example, such as lighting, will travel at a higher frequency than that of sound energy.
• can a wave length be measured
• Yes. There are special devices to do so.
• Why are hearing aids made of plastic (ignore this question)? Is it possible if we put aluminum in the form of a hearing aid in the ear that we will hear better?
• Not to be an answer....