sound Flashcards
transmission of sound
the process of sound waves traveling through a medium or object.
speed of sound in air and steel
speed of sound in air is 332 m/s and 5940 m/s
sound wave
a vibration that propagates through a medium as a mechanical wave
amplitude and frequency of wave
the maximum displacement or distance that a wave oscillates from its rest position, whereas the number of complete oscillations per second.
vibration
a rapid back-and-forth movement or oscillation
the mean position and extreme position of particles in vibration
The position when there is no net force acting on it, also known as the equilibrium position, is the position of maximum displacement from the mean position.
noise pollution
the loudness of sound produces discomfort in the ears.
causes of noise pollution
sounds of running vehicles and their horns blowing.
Various machines in factories make loud sounds.
examples of noise
machines, firecrackers and thundering of the clouds are considered noisy
on what conditions does music become noise?
When music becomes very loud, repetitive, and distorted, the music becomes noise.
audible sound
the range of frequency pf a sound wave that lies between 20Hz to 20000 kHz.
formula of height, wavelength, frequency, time period, speed of sound, intensity of a sound
height (s)= v x t
frequency <f> = no.of oscillations per time period or speed of sound by wavelength.
time period<t>= 1per frequency
wavelength = lambda= v / f
speed of sound <v>= f x wavelength
intensity of a sound <i> = power per area</i></v></t></f>
a list of factors affecting the speed of sound in a gas medium.
Temperature: as temperatures increase, gas molecules move faster, leading to quicker transmission of sound waves.
Molecular Mass of the gas: gases with lower molecular weight allow sound to travel faster than heavier gases.
Pressure: in an ideal gas, pressure changes proportionally with density, so the speed of sound remains unchanged.
Density: A denser gas medium resists movement more, slowing down sound propagation.
prove experimentally that the speed of sound is more in a solid medium than in air.
to demonstrate that the speed of sound is greater in a solid medium than in air
materials required: a long metal rod, a stop watch, arubber mallet, two helpers, a slethoscope.
procedure:
step 1: set up the experiment
1. place one end of the metal rod near your ear.
2. have a friend stand at the other end of the rod , afew metres away.
3. ask them tos trike the ord gently witha mallet while another person starts the stopwatch.
step 2: compare sound transmission in solid vs air
1. oberservation through solid rod.
Place your ear directly against the rod.
- your friend strikes the rod with the mallet.
- you will hear the sound immediately through the rod
2. second observation through the air.
- Now, move your ear away from the ord.
- your friend strikes the rod again.
You will hear the same sound a fraction of a second later through the air.
conclusion Since you hear the sound later through the solid rod than through the air, it proves that sound travels faster in solids than in gases.
longitudinal wave and what is it made up of?
a type of wave in which the particles of the medium move parallel to the direction of wave propagation.
It is made up of: compression: the region where particles are close together and are of high pressure in the wave.
rarefaction: regions where particles are spread apart and of low pressure in the wave.
transmission of sound and its type required for it?
the process by which sound waves travel through a medium from a source to a receiver. type sof sound required for it are solid, liquid or gas medium to propagate as sound wave are carried by the molecules within that medium.
sources of noise pollution in your school’s surroundings
construction of buildings and other projects.
playing loudspeakers and bands.
various machines in factories
sounds of running vehicles and their horns blowing.
movement of chairs and desks in classrooms
shouting and loud talking in hallways and playgrounds
causes and effects as well as controls of noise pollution.
introduction:
noise pollution is the loudness of sound which produces discomfort in the ear.
causes of noise pollution
increasing urbanization and vehicloe usuage.
uncontrolled use of loudspeakers.
lack of awareness about the harmful effects
industrializationa dn construction without proper osund proofing.
effects
a regualr and loud noise in the environment can lead to serious health problems like anxiety, irritation, hypertension, stress, lack of memory and concentration in studies or works.
a constant loud noise reduces teh hearing power or damages the ears temporarily or permanently.
this amkes it inconvenient to talk to other people.
Regular lack of sleep or insomnia during the night is bad for health.
controlling
silencing devices must be installed in aircraft, engines, transport vehicles, industrial machines, etc
the firing of crackers should be avoided
the horns of motor vehicles should not be blown unnecessarily
Noise-making factories and airports should be shifted away from residential areas.
Conclusion: a growing problem in our locality, affecting our productivity and the environment. However, through awareness, better planning, and responsible behavior, we can reduce noise pollution.
Why lightning and thunder takes place in the sky at the same time and at the same distance, but lighting is seen earlier and thunder is heard after.
the speed of sound is less than the speed of light. the speed of light in air is 3x 10 to the power of 8 m/s and the speed of sound in air isn 332 m/s. Because of this, the sound of a thunder is heard after than flash of lightning. this time interval between the flash of lightning we see and the sound of a thunder we hear depends on the height of clouds. nearer the clouds, less the time interval this is the reason why thunder is heard some time after the flash of lighning.
why is the speed of sound in gas medium the least?
their molecules are far apart, interacting weekly, and the medium is highly compressible, hindering efficient energy transfer.
in space, astronauts use an electrical medium to talk to each other.
sound needs a medium to travel, and space is a vacuum, so astronauts use radio waves which can travel through space to communicate.
when a ringing bell is touched, sound is stopped.
Sound is produced by vibrations traveling through our ears as osund waves. When a ring bell is touched, our hands absorb the energy of the vibration, so we are essentially stopping those vibrations.
wavelength
a distance over which a wave completes one cycle of its oscilliation.
