User:Cheerleaderr

From Wikipedia, the free encyclopedia

water waves, microwaves, sound waves, radio waces, and all other tpyes of waves transfer evergy from one plave to another.

wter waves are probably the easiest type of wave to visualize.

only energy carried by the waves move forward.

waves- rhythmic disturbance that carry energy through matter or space.

water waves transfer energy through the water. Earthquakes transfer energy in powerful waves that travel through Earth.

Both types of waves travel through a medium

medium- a material through which a wave transfers energy.

This medium may be a solid, a liquid, a gas, or a combination of these.

Radio waves and light waves, however, are types of waves that can travel without a medium.

Two types of waves carry energy.

These are transverse and compressional waves.

transverse waves- the medium moves at right anges to the direction the wave travels.

crests- the highest points of a wave.

troughs- the lowest points of a wave.

waves are measured by their wavelength

wavelength- the distance between a point on one wave and the identical point on the next wave, such as from crest crest or trough or tough.

amplitude- the distance from the crest (or trough) of a wave to the rest position of the medium.

the amplitude corresponds to the amount of energy carried by the wave. waves that carry great amounts of energy have large heights or amplitudes, and waves that carry less energy have smaller amplitudes.

frequency- the number of wave crests that pass one place each second.

frequency is expressed in hertz (Hz).

One hertz is the same as one wave per second.

as the frequency increses the wavelength decreases.

wave velocity, v, describes how fast the wave moves forward.

velocity = wavelength x frequency

     v      (lambada)          f

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sounds are produced by the vibrations of your own vocal chords.

the energy produced by these vibrations is carried to your friends ears by sound waves.

compressional waves- a type of wave where matter vibrates in the same direction as the wave travels.

the crowded area is called a compression.

the less dense area of the wave is called a rarfaction.

a wavelength in a compressional wave is made of one compression and one rarefaction.

the frequency is the number of compressions that pass a place each second.

the vibrations gernerated by your vocal cords produce compressional waves that travel through the air to your friend. this process is similar to what you saw when you made compressional waves on a spring.

Your voice causes rarefactions among the particles in the air.

the speed of soundwaves depends on the medium through wich the waves travel and the temperature of the medium.

air is the most common medium through which you hear sound waves.

sound waves can be transmitted through any type of matter.

liquids and solids are even better conductors of sound than air is because the individual particles in a liquied or solid have greater influince on eahc other than the particles in air making the transmission of evergy easier.

the temperature of the medium is also an important factor in determining the speed of sound waves.

as the temperature of a substance increases, the molecules move faster and therefore collide more frequintly.

you see the light before you hear the sound becuase light waves travel through air about 1 million times faster than sound waves do.

making sense of these waves incolces three stages: the gathering and amplification of the compressional waves bu the ear mechanism, the conversion of these waves into nerve inpulses and the decoding of these signals in the brain.

sound detectors such as microphones collect and convert kinetic energy from the moving particles in sound waves into another form of energy, usually electrical energy.

your ear is a versatile sound dtector. it is sensitece to a range of intensities and frequincies.

pitch- the highness or lowness of a sound.

the pitch you hear depends on the frequency of sound waves

the higher the frequency the higher the pitch the lower the frequency the lower the pitch

a healthy human ear can hear aound frequencies from about 20 Hz to 20,000 Hz. As people ages the often have some trouble hearing high frequencies.

most people cant hear sound frequencies above 20 Hz which are called ultrasonic waves

infrasonic waves are below 20 Hz

intensity- depends on the amount of energy in each wave.

intensity increases as the amplitude increases

loudness- the human perception of sound intensity.

the higher the intensity and the amplitude, the louder the sound

the intensity level of a sound is measured in units called decibels (abreviated dB)

the faintest sound that can be heard by humans is 0dB

over 120 dB may cause pain and permanent hearing loss

rock concerts (intensity level)

Doppler effect is a change in wave frequency the doppler effect is observed when the source o sound is moving relatice to the observer.

the sound waves carried energy to your ears through a series of compressions and rarefactions of aire molecules.

the more intence the waves, or the more energy they carry, the louder your clock sounds