# Sound and Light Ch. 1

## 33 terms

### Wave

A disturbance that transfers energy from place to place

### Energy

The ability to do work

### Medium

Material through which a wave travels

### Mechanical Wave

A wave that requires a medium through which to travel

### Vibration

A repeated back-and -forth or up-and -down motion

### Transverse Wave

A wave that moves the medium in a direction perpendicular to the direction in which the wave travels

### Crest

The highest part of a transverse wave

### Trough

The lowest part of a transverse wave

### Longitudal Wave

A wave that moves the medium parallel to the direction in which the wave travels

### Compression

The part of a longitudal wave where the particles of the medium are really close together

### Rarefaction

The part of a longitudal wave where the particles of the medium are far apart

### Surface Wave

A wave that occurs at the surface between two mediums

### Amplitude

The maximum distance the particles of a medium move away from their rest positions as a wave passes through the medium

### Wavelength

The distance between two corresponding parts of a wave

### frequency

The number of complete waves that pass a given point in a certain amount of time

### Hertz (Hz)

Unit of measurement for frequency

### Reflection

The boucing back of of a wave when it hits a surface through which it cannot pass

### Angle of Incidence

The angle between an incoming wave and an imaginary line drawn perpendicular to the surface of the new medium

### Angle of Reflection

The angle between a reflected wave and an imaginary line drawn perpendicular to the surface of the new medium

### Refraction

The bending of waves as they enter a different medium

### Diffraction

The bending of waves around a barrier

### Interference

The interaction between waves that meet.

### Constructive Interference

The interference that occurs when two waves combine to make a wave with a larger amplitude

### Destructive Interference

The interference that occurs wen two waves combine to make a wave with a smaller amplitude

### Standing Wave

A wave that appears to stand in one place, even though it is really two waves interfering as they pass through each other

### Node

A point of zero amplitude on a standing wave

### Antinode

The point of maximum amplitude on a standing wave

### Resonance

The increase in the amplitude of vibration that occurs when external vibrations match the object's natural frequency

### Seismic Wave

A wave produced by an earthquake

### Primary Wave

A longitudal seismic wave

### Secondary Wave

A transverse seismic wave

### Tsunami

Surface wave on the ocean caused by an underwater earthquake

### Seismograph

Instrument used to detect and measure earthquakes