Stage Plan Overview: Before Lesson: Prep all materials required and make the appropriate photocopies.
Inform students that they will continue to learn about sound and the impact of sound on our daily lives.
Ask students what they think the loudest noise in the world is? Have a talk / ask them to list out some ideas!
Go through Teacher Resource 1 – Top Ten Loudest Sounds. Ask students if they think that this list is accurate and see if they can suggest other noises which could match these noises? If sensible, the students can have a ‘Scream’ competition to who can project their voice the loudest (Only if the students you have are sensible enough!)
Ask students if they know what a “Decibel” is? Introduce the concept of “Decibels” to the class and read through Teacher Resource Sheet 2 for further understanding.
For further understanding then ask students to list out several different sounds and what they think the decibel levels are? Then go through Teacher Resource Sheet 3 “Typical Sound Levels” and look at all the different examples of sounds and their decibel levels.
Students will then read and fill in the gaps for Activity Sheet 1 “Sound Travels”. Answers are on Teacher Resource Sheet Number 4
To further their understanding and comprehension then students will then do Activity Sheet 2 “Noise”. Answers are on Teacher Resource Sheet Number 5
Main Tasks: Continued:
The students will then do the Muffling Sound Experiment which is on Activity Sheet 3.
There is a list of materials which can be used but you can improvise and use additional materials (Just as long as it is safe)
List the materials you will test in the table given and then make a prediction of which you think will muffle the sound best and how?
You can use this YouTube videoto make the sound - YouTube video – Fail Sound: https://www.youtube.com/watch?v=m30mG3JKzA8 ) – Via iPad
You can repeat this several times to see if the results are consistent.
For the Activity Sheet 4 “Make Your Own Instruments” experiment, please ask students to select one simple instrument to make.
Try and devise a tune with some rhythm. You can film this if you wish!
Top Ten Loudest Sounds Teacher Worksheet 1:
Loud noises occur every day. Wincing at the annoyance of a dog bark, or covering your ears as you pass a construction site is the standard way to guard against the harsh sounds. The pain threshold for humans is 120-130 Decibels. Any sound above 85 dB can cause hearing loss, and the loss is related both to the power of the sound as well as the length of exposure. Here are 10 sounds produced throughout history and how incredibly loud they are. Just remember, human speech is only registered at about 25-35 decibels.
10. Rock Concert/Speakers
A 400,000 Wat rock concert or a similar set of speakers mounted in a vehicle can reach ear-splitting decibel levels. Is it any reason most promoters recommend you wear ear protection to stave off the 135-145 decibel sound waves?
Though not typically heard up close, fireworks are still explosions and are very loud. The sound heard from the sky is pretty loud, though not damaging, but at the bursting point the decibel levels reach a staggering 145-150. Even tests are performed under strict sound proofing to avoid any ear injury.
Teacher Worksheet 1 Continued:
Gunfire for anyone unfortunate enough to be standing near it can be quite damaging to the ears registering at a quite loud 145-155 decibels. This is the very reason why you should always wear ear protection when on a firing range.
7. NHRA Dragsters
Sitting next to a dragster as it fires up its engines and screams down the raceway can be more than just loud; it can be damaging to your entire body. At the 155-160 Decibel range not only will it severely to permanently damage your hearing, but it also vibrates your vision and makes it temporarily difficult to swallow. That’s why no one stands next to them.
Teacher Worksheet 1 Continued: 6. Space Shuttle Launch
When the rockets fire, it is wise and, in fact, fully enforced, that you stand at least a half-mile away lest you get inundated by 165-170 decibels of painful sound. Unlike many other loud noises, the shuttle rocket sound is constant as it creates the thrust necessary to lift it from the ground.
5. The Blue Whale
Blue whales mostly emit very loud, highly structured, repetitive low-frequency rumbling sounds that can travel for many miles underwater. These songs may be used for communicating with other blue whales, especially in order to attract and find mates. The call of the blue whale reaches levels up to 188 decibels. This extraordinarily loud whistle can be heard for hundreds of miles underwater. The whale is the loudest, and, the largest animal on earth.
Teacher Worksheet 1 Continued:
4. Volcano – Krakatoa
The 1883 the Krakatoa eruption ejected more than 25 cubic kilometres of rock, ash, and pumice and generated the loudest sound historically reported at 180 Decibels: the cataclysmic explosion was distinctly heard as far away as Perth in Australia approx. 1,930 miles (3,110 km), and the island of Rodrigues near Mauritius approx. 3,000 miles (5,000 km).
3. 1-Ton TNT Bomb
Standing as close as 250 feet away from the impact, the resulting explosion from a 1 ton bomb creates a decibel count of 210. Without sufficient hearing protection, not to mention a complete sound-resistant bunker surrounding you, you could quite literally die from the intense vibrations that would literally shake you apart. Unless, of course, you were under the bomb!
A sufficient enough quake to rend the ground in twain and destroy buildings, whole rock, and human life reaches a decibel level of 235. If you are caught in the epicentre and are unlucky enough to not be above the ground in a plane or helicopter, the intense noise and vibrations could kill you long before death by any falling object.
1. Tunguska Meteor
The Tunguska event was a massive explosion that occurred near the Podkamennaya (Under Rock) Tunguska River in what is now Krasnoyarsk Krai of Russia, at 7:40 AM on June 30, 1908. The explosion was most likely caused by the air burst of a large meteoroid or comet fragment at an altitude of 5 to 10 kilometers (3–6 mi) above Earth’s surface. It was measured with the similar impact of a 1000-Mega-ton bomb with a decibel rating 300-315. This is often considered to be the loudest single-event in history.
Teacher Worksheet 2:
The decibel (abbreviated dB) is the unit used to measure the intensity of a sound. The decibel scale is a little odd because the human ear is incredibly sensitive. Your ears can hear everything from your fingertip brushing lightly over your skin to a loud Jet. In terms of power, the sound of the jet engine is about 1,000,000,000,000 times more powerful than the smallest audible sound. That's a big difference!
On the decibel scale, the smallest audible sound (near total silence) is 0 dB. A sound 10 times more powerful is 10 dB. A sound 100 times more powerful than near total silence is 20 dB. A sound 1,000 times more powerful than near total silence is 30 dB.
Here are some common sounds and their decibel ratings:
Near total silence - 0 dB
A whisper - 15 dB
Normal conversation - 60 dB
A lawnmower - 90 dB
A car horn - 110 dB
A rock concert or a jet engine - 120 dB
A gunshot or firecracker - 140 dB
You know from your own experience that distance affects the intensity of sound -- if you are far away, the power is greatly diminished. All of the ratings above are taken while standing near the sound.
Any sound above 85 dB can cause hearing loss, and the loss is related both to the power of the sound as well as the length of exposure. You know that you are listening to an 85-dB sound if you have to raise your voice to be heard by somebody else. Eight hours of 90-dB sound can cause damage to your ears; any exposure to 140-dB sound causes immediate damage (and causes actual pain).
Teacher Worksheet 3:
Teacher Worksheet 3 Continued:
Teacher Worksheet 4:
Sound Travels: Answers
When you bang a drum the vibrating drum makes the air near it vibrate. The vibrations in the air travel to the ears, and you hear the sound. Sound cannot travel in space because there is no air for the vibrations to travel through. Space is a vacuum. That is why astronauts need to use radios to talk to each other. Air is a gas. Sound can travel through gases. Sound can also travel through liquids and solids. In air, sound travels at 340 m per second, but speeds up in water to 1,500 m per second.
Dolphins communicate with each other under the sea. The sound can travel for hundreds of miles, much further than in air. Sound travels even more quickly through a solid metal than through the air or water. Standing near a railway line, a humming from the rails can be heard several minutes before the train itself can be heard. Use the words below to complete the sentences.
Teacher Worksheet 5:
Noise! Answer Sheet
There are some sounds that we do not want to hear. A sound may be too loud, like the sound made by very loud machinery, or it may be annoying, like music that you do not like. Sounds like this are called noise.
Very loud sounds can damage your ears. You can protect your ears by wearing special ear protectors made out of soft materials. The soft materials absorb the vibrations and make them quieter. You can make sounds quieter in a house by using soft materials such as carpets and curtains.
Activity Sheet 1:
When you bang a drum the vibrating drum makes the air near it ________________. The vibrations in the __________ travel to the __________, and you hear the sound. Sound cannot travel in __________ because there is no air for the vibrations to travel through. Space is a __________. That is why astronauts need to use _________ to talk to each other.
Air is a __________. Sound can travel through gases. Sound can also travel through __________ and __________. In air, sound travels at __________ per second, but speeds up in water to __________ per second.
Dolphins communicate with each other under the _____. The sound can travel for hundreds of __________, much further than in air. Sound travels even more __________ through a solid metal than through the air or water. Standing near a railway line, a ____________ from the rails can be heard several minutes before the train itself can be heard.
Use the words below to complete the sentences.
Activity Sheet 2:
There are some __________ that we do not want to hear. A sound may be too __________ like the sound made by very loud machinery, or it may be annoying, like music that you do not like. Sounds like this are called __________.
Very loud sounds can _________ your ___. You can __________ your ears by wearing special ear __________ made out of soft materials. The soft materials __________ the __________ and make them __________. You can make sounds quieter in a house by using soft _________ such as __________ and curtains.
Activity Sheet 3 Some jobs require protective ear equipment to muffle or deaden sound. Some materials are much better than others at muffling sound. You are going to test a range of materials to see which seems to be best for this purpose. You will try to muffle the sound of your choice (You can use this youtube video – Fail Sound https://www.youtube.com/watch?v=m30mG3JKzA8 ) BEFORE YOU START: List the materials you will test in this table and then make a prediction of which you think will muffle the sound best.
Number them 1-4 with 1 being the best and 4 the least effective.
Materials – Cotton Wool, Ear Plugs, Headphones and Fingers!
What will you do to make it a fair test?
What variables will you change? .............................................................................................
Activity Sheet 3 Continued: What variables will you keep the same? ……………………………………………………………………………