A Wave on a String
Wall
String at rest.
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A string is fastened to the wall at one end
And held by your hand at the other
A Wave on a String
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You pull the string upwards by an upward force, F.
The first particle of the string is pulled upwards
Due to intermolecular forces, the particle next to it will move upwards
a moment later
This particle causes the one next to it to move up
A Wave on a
String
U
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You then pull the string down
Once the first particle has reached its highest point
(known as the amplitude), it is pulled downwards
The particle next to it is still rising and later reaches its highest point
The second particle, is then pulled downwards
A Wave on a
String
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This produces an arc shape, or a “wave”
The wave “moves” down the length of the string, particle by particle
Do the particles of the string move from left to right ?
A Wave on a
String
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Energy is transferred from one end of the string to the other
Particles vibrate in place
But no particles of the string actually change location or translate
The string acts as a medium across which mechanical energy is transfered
A Traveling Wave
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The arc shape can be described as a waves function, f(t).
The wave energy moves with velocity, v
Class notes:
- Traveling wave
- Simple Harmonic Motion
- Anatomy of a wave