By Connie ChuBy Connie ChuPeriod APeriod A

Physics ProjectPhysics Project

NoiseNoise• Noise is any loud, discordant,

or disagreeable sound–Whether something is noisy or not is

determined by the person

• Noise is also a type of sound

How do we determine noise?How do we determine noise?• Noise is determined by how intense the

sound is– Intensity is the rate at which energy flows perpendicular to the direction of

wave motion

– It is also how loud a sound is

– The unit for intensity is watts per square meter (W/m2)

Is It Possible to Measure Noise?Is It Possible to Measure Noise?

• Although noise cannot be seen, smelt, tasted, or physically felt, it can actually be measured by the decibel scale in levels– Decibel is a (dimensionless) unit that measures the ratio of the intensity

of a sound wave to the intensity at the threshold of hearing

• The threshold of hearing is the lowest point on the decibel level that can be heard by the human ear

– The symbol for decibel is dB

• Because loudness and intensity aren’t exactly directly proportional, they’re measured by a logarithmic method

Can noises be too loud?Can noises be too loud?• When noises become too loud or intense,

they exceed the threshold of pain– The threshold of pain is the point on the decibel level

where noise causes pain when heard by the human ear

• To prevent hearing loss or pain from loud noises, workers or musicians wear mufflers or special types of earmuffs to muffle or block out the sound as well as to protect their ears

Examples Decibel Level (dB) Intensity (W/m2)

Threshold of hearing 0 1.0 x 10-12

Rustling leaves 10 1.0 x 10-11

Whisper 20 1.0 x 10-9

Mosquito buzz 40 1.0 x 10-8

Normal conversation 60 1.0 x 10-7

Vacuum cleaner 70 1.0 x 10-5

Traffic 80 1.0 x 10-4

Lawn mower 90 1.0 x 10-3

Subway 100 1.0 x 10-2

Rock concert 110 1.0 x 10-1

Threshold of pain 120 1.0 x 100

Machine gun 130 1.0 x 101

Nearby jet plane 150 1.0 x 103

How can noise be pollution?

Noise PollutionNoise Pollution• Noise can be a type of pollution by

being irritating to a person or by bothering groups of people as well as disturbing natural habitats if it is excessively loud

• There are 2 types of noise pollution:–Those that exceed the threshold of pain

–And those that are annoying

Have you ever been a victim of noise pollution?

Examples of Noise PollutionExamples of Noise Pollution• Hallways at Rush• People blasting up their car stereos• Airplane flying by at night• Your next door neighbor having a huge party and talking and

blasting music real loud while you’re trying to do homework• Those loud motorcycles that speed at night and wake you up• Traffic jams• Birds chirping at dawn• Car alarm going off• Those “bomb” fireworks• Freight trains• Lawnmower• Construction workers building something

…if you’ve experienced any of the above and became annoyed or disturbed, then you’ve been a victim of noise pollution

Can noise pollution be deadly?

Health EffectsHealth Effects• Depending on the person, environment, the type

of noise(s), and how the person reacts with any of them, noise pollution, if exposed to it many times, can be deadly

• The most common form of health risk is that it can cause high blood pressure and hearing loss

– A person can have an increase in blood pressure if he/she becomes extremely mad or irritated every time the noise happens and can do nothing about it.

– A person can have hearing loss if exposed too many loud noises and they don’t wear any protective gear

Other Health EffectsOther Health Effects• Hearing a lot of noise can also make you more

stressful since it becomes very irritating and the fact that you have to deal with it every day– Becoming more stressful causes problems with the nervous, digestive,

and cardiovascular system

• It can give you headaches because of stress and irritation– Headaches are related to the nervous system

• Because hearing too much noise can cause high blood pressure, you become more at risk for heart disease

• It can disrupt your sleep if a loud noise wakes you up constantly– Lack of sleep means you can’t function correctly

If noise pollution affects humans, can it affect animals?

The answer: YesThe answer: Yes• Not only does noise cause problems for us, but it can also

make things worse for animals• The most common effect noise pollution causes is the

disturbance of habitats and natural senses– For example, loud noises can scare away birds and may cause them to migrate

to a different area as well as leaving their nests unprotected

• Not only that, but it also limits or reduces animals’ usable habitats

– As for natural senses, a bat, being able to hear beyond our threshold of hearing, wouldn’t be able to fly correctly if it hears too many noises or too many loud noises—it’d crash into buildings or objects

• Noise doesn’t always cause problems for animals that fly, it can cause problems for predators since they use their hearing to catch their prey

• It can also cause reproduction problems since some animals use mating calls to attract the opposite gender

If noise pollution can cause bad health effects, disturb natural habitats as well as being very annoying and loud, is the government doing anything to minimize it?

The answer: SomewhatThe answer: Somewhat• An organization called the U.S. Environmental Protection

Agency has laws regarding all types of disturbances, pollution, radiation, pesticides, animals’ natural habitats, and natural disasters– They used to control all noises through their Office of Noise Abatement and

Control

– They used to have laws called the Noise Control Act of 1972 and the Quiet Communities Act of 1978 to limit the use of machinery, appliances, transportation vehicles such as planes and trains, and other commercial merchandises

– Although they’re still in effect today, by 1981, Congress decided it was best to let the state or local government handle noise pollution

• Some natural parks have a limited amount of how many vehicles, people, and sightseeing flights to reduce noise pollution in the wilderness

If noise pollution causes so much problems, how come the government isn’t doing any immediate or strict actions?

The Reasons: Private Property, Controversial Topic, The Reasons: Private Property, Controversial Topic, and Not Toxicand Not Toxic

• Noise pollution is considered a “controversial” topic because:– Some people don’t believe noise pollution exists since there’s noise

everywhere

– An example: People who live near noisy areas, such as near airports, complain about planes taking off and landing, but the city governments say that they should’ve known when choosing there to live

• The government also can’t do anything if your noisy object is on private property– For example, no one is going to arrest you for cutting your grass

• Another reason why noise pollution isn’t such a major concern is because when compared to air, water, and land pollution, it isn’t toxic and extremely life threatening– Also, noise isn’t something you can see, taste, smell, or touch so people

don’t think it’s a big deal

How can you prevent noise pollution?

The most easiest and simplest way to reduce noise is to talk

quieter and softer.

Are there places in the world where noise doesn’t exist?

Well there are places…Well there are places…• Called libraries that prohibit noise and noise pollution• As for an actual answer, I don’t know but I can give you my

theory:– I believe that places without any modern electronic technological devices, such as

cars, radios, etc. and barely or no animals or humans that inhabit the area, have no noise

– Examples are:

• Parts of Antarctica

• The very bottom of the ocean

• Parts of Greenland

• Parts of northern Canada, Alaska, Russia, Sweden, and Norway

• At the peaks of mountains

• Deserts (the ones with nothing but sand and snow)

• Places that have a vast grassland with no trees or little shrubs

• Sound recording studios

• Places that have had a nuclear meltdown

ReferencesReferences1. http://www.physicsclassroom.com/class/sound/u11l2b.cfm2. http://www.epa.gov/

– http://www.epa.gov/air/noise.html– http://www.epa.gov/history/topics/noise/index.htm

3. http://www.nonoise.org/– http://www.nonoise.org/aboutno.htm – http://www.nonoise.org/library/fctsheet/wildlife.htm

4. http://www.howstuffworks.com/question124.htm 5. Textbook

– Vocabulary pages 416-417– Noise pollution pages 442-443