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What is sound? |
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Sound is anything that can be heard and is a form of energy. |
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Why do we use sound? |
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We use sound to communicate with others to find out about what’s going on around us |
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What is energy? |
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Energy is the ability to make things move. It is needed to start the vibrations that make sound. |
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How is sound made? |
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Sound is made by the vibrations of an object. To make a sound all or part of the object has to vibrate. |
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What are vibrations? |
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Vibrations are the back and forth movements of an object. Vibrations can be powerful, weak, fast or slow. |
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How do your vocal cords produce sound? |
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vocal cords (2leathery flaps with space between for air) when you speak they move closer causing them to vibrate & create sound |
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Energy comes in many forms. Name 6 types |
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Chemical energy, Heat energy, Electrical energy, Energy of motion, Solar energy,Sound energy |
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Chemical energy |
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chemical bonds hold together the tiny particles that make up everything. When the bonds are broken, energy is released. |
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Heat energy |
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goes from warm things to cold things. |
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Electrical energy |
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flows along electrical lines and gives an iron, for example energy. |
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Energy of motion |
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anything that moves has this kind of energy |
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Solar energy |
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the sun produces this energy for all living things on earth. |
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Sound energy |
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energy of vibrations. |
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How does sound travel? |
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Sound travels in waves that move in all directions. |
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Why is it harder to hear someone far away than close? |
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The farther sound waves travel, the weaker they get. |
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What are sound waves? |
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Sound waves are vibrations that make sound. |
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How are sound waves different than water waves? |
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Sound waves out in all directions (to each side, up and down and all around) Water waves only move along the surface of the water. |
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How does the telephone send the sound of our voices far away? |
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phone takes sound energy from voice & changes to electrical energy & travels along telephone lines & is changed back to sound energy on the other end |
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How do sound waves travel? |
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Sound waves travel away from it’s source in all directions. |
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What does sound travel through? |
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Sound travels through solids, liquids and gases. |
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How does sound travel through solids? |
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In solids sound travels the fastest because molecules are close together. |
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How does sound travel through liquids? |
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In liquids sound travels the second fastest because the molecules are farther apart in liquid than solids. |
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How does sound travel through gases? |
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In gases sound travels the slowest because the molecules are the farthest apart. |
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What is an echo? |
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An echo is sound waves bouncing back from a hard surface. When it bounces back it is reflected an sounds like the original sound. |
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Name the five parts of the ear. |
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The five parts of the ear are:
(1) outer ear (2) ear canal (3) eardrum (4) middle ear (5) inner ear |
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Explain how we hear. (outer ear) |
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Sound waves are first collected by the outer ear. The sound wave travels down the ear canal to the eardrum. |
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Explain how we hear. (middle ear) |
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When the sound waves hit the eardrum it will vibrate.These vibrations then travel to the middle ear. |
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Explain how we hear.(middle ear) |
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In the middle ear they are passed on to three small bones called the hammer, the anvil and the stirrup. |
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Explain how we hear.(inner ear) |
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The bones then pass the vibrations on to the cochlea which is in the inner ear. |
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Explain how we hear.(inner ear) |
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Nerves in the inner ear carry the message of these vibrations to the brain. |
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Explain how we hear |
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sound->vibrate eardrum->bones->conchlea->nerves->brain |
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What is frequency? |
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Frequency is the # of vibrations an object makes in a certain amount of time. It is measured in hertz (Hz). High is alot and low is a few. |
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Name 2 animals that can hear high frequency? |
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Bats and dolphins can hear at high frequencies. |
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What animal communicates using low sound? |
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An elephant uses low sound to communicate. |
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What is volume and pitch? |
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The loudness or softness of a sound is volume. The highness of lowness of a sound is pitch. |
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Define amplitude. |
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A loud sound has a high amplitude. A low sound has a low amplitude. |
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How is sound measured? |
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Sound is measured by the number of cycles the sound wave makes in a second. |
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How is volume (loudness) measured? |
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Volume is measured in decibles. The number of decibles tells us how powerful a sound is. Ex: a whisper is 20db and a jet taking off is 140db |
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What is noise pollution? |
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Loud and constant noise is noise pollution. |
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How can you protect your ears from noise pollution? |
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(1) wear earplugs (2) soundproof rooms |
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How is sound technology used? |
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Sound technology is used: (a) by advertisers (b) to do x-rays or ultrasound (c) for cleaning very small devices |
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What is amplification? |
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Amplification is the process of making sound louder. |
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Who invented the telephone? |
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Alexander Graham Bell invented the telephone in 1876. |
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Who invented the world’s first electronic synthesizer t play music? |
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Hugh LeCaine built the first electronic synthesizer in 1945. |
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