Term
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Definition
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Term
| How does the sound made by a vibrating speaker get to your ears? |
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Definition
| When an object like a radio speaker vibrates, it collides with nearby air molecules in the air, transferring some of its energy to them. These molecules then collide with other molecules in the air and pass the energy on to them. This process of collisions and energy transfer forms a sound wave. Eventually, the wave reaches your ears and your brain interprets them to hear a sound. |
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Term
| Why is sound a compressional wave? |
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Definition
| Compressional waves are made up of two types of regions called compressions and rarefactions. The object that vibrates makes nearby molecules in the air push together to form compressions, and when it travels out, it has room to spread out. This creates a rarefaction. |
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Term
| How does sound travel as a wave? |
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Definition
| The compressions and rarefactions move away from the speaker. A series of compressions and rarefactions forms that travels to your ear. This wave is what you hear. |
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Term
| How do sounds reach your ears when objects are in the way? |
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Definition
| Sound can move through any type of matter- solid, liquid, or gas. |
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Term
| What would happen if no matter existed to form a medium? Could sound be transmitted without particles of matter to compress, expand, and collide? |
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Definition
| No. In situations like space, where there is no matter, there is no sound. |
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Term
| What is the speed of sound through different mediums? |
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Definition
| In general, sound travels slowest in gases, faster through liquids, and even faster through solids. |
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Term
| What factor affects the speed of sound waves? |
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Definition
| Temperature. This is because when the temperature of a substance rises, the molecules move faster, making it more likely to collide with one another. |
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Term
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Definition
| The outer ear is the visible part of your ear. It consists of your ear canal and the eardrum. |
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Term
| How does the outer ear gather sound waves? |
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Definition
| Your outer ear is shaped to help gather and direct sound into the ear canal, which is a passageway. The sound waves travel along this passageway, which leads to the eardrum, a tough membrane. When incoming sound waves reach the eardrum, they transfer their energy into it and it vibrates. |
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Term
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Definition
| Three tiny bones, the hammer, the anvil, and the stirrup, create the middle ear. |
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Term
| How does the middle ear amplify sound waves? |
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Definition
| When the eardrum vibrates, it passes the sound vibrations into the middle ear, where the bones start to vibrate. They make a lever system that multiplies the force and pressure exerted by the sound wave. The bones amplify the sound wave. The stirrup is connected to a membrane on a structure called the oval window, which vibrates when it does. |
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Definition
| The inner ear consists of cochlea, which is a spiral-shaped structure that is filled with liquid and contains tiny hair cells. |
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Term
| How does the inner ear convert sound waves? |
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Definition
| When the membrane in the oval window vibrates, it is transmitted into the inner ear. The tiny hair cells in the cochlea begin to vibrate, nerve impulses are sent through an auditory nerve to the brain. The cochlea convert sound waves to nerve impulses. |
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Term
| Where are electromagnetic waves? |
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Definition
| They are everywhere! They enable us to see. They make our skin feel warm, etc. |
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Term
| How do sound and water waves travel? |
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Definition
| They travel because energy is being transferred from particle to particle. Without matter to transfer the energy, they could not move. |
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Term
| How do electromagnetic waves move? |
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Definition
| They do not require matter to transfer energy. They travel by transferring energy between electric and magnetic fields. |
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Term
| How are electromagnetic waves created? |
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Definition
| They are created by vibrating electric charges. |
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