# Ch. 11 Science

## 43 terms

waves transport:

### frequency x wavelength

formula: wave speed =

### wave speed = frequency x wavelength

formula for wave speed can also be written as:

### transverse wave

direction of wave travel is perpendicular to the vibrating source

### longitudinal wave

direction of wave travel is along the direction in which the source vibrates

### longitudinal wave

vibrations of this wave are parallel to the direction of energy transfer. wave of compression can travel along it and between compressions are rarefractions

### compressions and rarefractions

make up the longitudinal wave and travel in the same direction

### longitudinal wave

what kind of wave is sound?

high frequency =

### air molecules

what are set into vibration when next to a vibrating object?

### 330 m/s, dry air at 0° C

speed of sound is usually ______ in what type of climate at what temperature ______

### echo

reflection of sound is called a(n)

### law of reflection

the angle at which sound strikes a surface is equal to the angle of reflection. this is called:

### reverberations

multiple reflections of sound

### acoustics

study of sound is called

### light

sound obeys the same laws of reflection as ______

### frequency of the sound

the speed of sound does not depend on:

### false

wind conditions, temerature, humidity, and the medium can not effect the speed of sound. True or False

### rigid

what kind of surface reflects sound more easily?

### bend

what do waves do when the speed of the wave changes from one place to another

### refraction

bending of sound as the speed changes from one place to another is called:

### forced vibration

the vibration of a factory floor due to machinery is an example of:

### natural frequency

when disturbed, any object made of an elastic material vibrates at its own special set of frequencies, which together form its special sound, this is called:

### resonance

when the frequency of forced vibrations on an object matches the object's natural frequency, a dramatic increase in amplitude occurs, this is called:

### sympathetic vibration

the resonant motion of a second object is often called:

### resonance

this occurs whenever successive impulses are applied to a vibrating object in rhythm with its natural frequency

### constructive interference

when crests of separate waves meet each other and result in a wave of increased amplitude

### interference

property of waves when they meet each other

### destructive interference

when the high portions of one wave fill in the low portions of another when they meet

### out of phase

when the regions where a crest of one wave overlaps the trough of another and it results in zero amplitude these waves are called:

### beats

______ are due to interference and result in a faint then loud then loud sound and so on

### standing waves

A pattern of vibration that simulates a wave standing still

### nodes

stationary parts of the rope/wave

### antinodes

positions on a standing wave that have the largest displacements are called:

### Doppler Effect

when the area something is moving towards gets a higher frequency than the area the object is moving away from

### hertz

the unit of frequency (per second)

### 1/frequency

formula for period is:

### sound wave

longitudinal vibratory disturbance that travels in a medium (20-20,000 hertz)

### wave

a disturbance of vibration propagated from point to point in a medium or in space

### 1/frequency

period equation is

### v=(upside down y) x f

wave speed formula

### longitudinal wave

a sound wave is a

### hot air and solids

sound moves faster in