ByAjay R

Presented ByVijay R

So yes! What is sound after all??

It’s just a form of energy. Isn’t that cool and simple as an icing on a cake?

Sound

Audible Inaudible

Yes! Sound is not always audible to us(humans)

It is also inaudible sometimes.

• Sound is audible to humans only in the range 20Hz to 20000Hz.Hz is pronounced as Hertz, it’s justthe unit of frequency• Below 20Hz we claim sound to be too dull to be heard• Above 2000Hz it is too strong to be heard

OKAY OF WHAT USE OF KNOWING THIS? LET’S FIND OUT….

Infrasonic waves can be heard only by Elephants, Cats And Dogs,Sorts of Snakes,…. On the other hand, ultrasonic waves are heard by bats, Dolphins,Toothed Whales,….

Do you know?Mosquitoes don’t like ultrasonic waves. Isn’t that cool??Here on goodbye to GOOD KNIGHT, ALL OUT,….All mosquitoes are resistant to them!Nowadays Android Apps are developed for this purposeEg. Anti Mosquito,…. They generate ultrasonic waves to keep

mosquitoes away!

Noise is something that is not symmetrical or it is Unpleasant To Us It is caused due to numerous reasons in our Surroundings

It is measured by a quantity called dB

(pronounced as decibel)

Sources of Noise

The noise pollution has two sources, i.e. industrial and non-

industrial

he industrial source includes the noise from various industries

and big machines working at a very high speed and high noise

intensity

Non- industrial source of noise includes the noise created by

transport/vehicular traffic and the neighborhood noise generated

by various noise pollution can also be divided in the categories ,

namely, natural and manmade

Road Traffic Noise

Air Craft Noise

Noise from railroads

Construction Noise

Noise in Industry

Noise in building

Noise from Consumer products

Sources of Noise

Noise Levels of Sources

Source Noise level dB Source Noise level,

dB

Air compressors 95-104 Quiet garden 30

Diesel generator 95 Ticking clock 30

Milling machine 112 Computer rooms 55-60

Power operated

portable saw

108 Type institute 60

Trucks 90-100 Printing press 80

Car horns 90-105 Sports car 80-95

Jet takeoff 120 Trains 96

Harmful Effects Decreases The Efficiency Of A Man

Lack Of Concentration

Fatigue

Abortion Is Caused

It Causes Blood Pressure

Temporary Of Permanent Deafness

Effect On Vegetation Poor Quality Of Crops

Effect On Animal

Effect On Property

Sleeplessness

Control of Noise Pollution

Noise Control at Source

Reducing the noise levels from domestic sectors

Maintenance of automobiles

Control over vibrations

Low voice speaking

Prohibition on usage of loud speakers

Selection of machinery

Maintenance of machines

Control of Noise Pollution

Control in the transmission path

Installation of barriers

Design of building

o Installation of panels or enclosures

o Green belt development

Using protection equipment

Job rotation

Exposure reduction

Hearing protection