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Science_Lab_Yellow / Lesson 4: What Is Volume?

 What is Volume What will we be learning today? In this lesson, we are going to learn all about what is volume.

 What Is Volume? A sound wave makes the molecules of gases in air vibrate. The back-and-forth distance they vibrate is based on how much energy the sound wave carries. The more the energy, the greater the distance. The more the energy, the greater the height of the wave as it appears on an oscilloscope. Which of the waves below is carrying more energy?

 What is the difference between a yell and a whisper? A sound's volume-how loud or soft it is-depends on the amount of energy in a sound wave. To make a louder sound with a rubber band, pluck it harder. A loud sound has more energy than a soft sound and produces a taller wave on an oscilloscope.

 You can also make a sound louder by increasing the amount of surface that vibrates. For example, when a cup is attached to a rubber band, the cup and rubber band vibrate together. Together they make a louder sound than just a rubber band alone.

 Volume is measured in units called decibels (dB) with an instrument called a decibel meter. On the decibel scale, a sound that measures 50 dB is 10 times louder than one that measures 40 dB. The same 50-dB sound is 100 times louder than a 30-dB sound-that is, 10 x 10 times louder. The 50-dB sound is 1,000 times louder than a 20-dB sound-10 x 10 x 10 times louder.

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