Thursday, 19 June 2014 10:13

## G3-02: SHIVE WAVE MACHINE - SUPERPOSITION OF PULSES

• ID Code: G3-02
• Purpose: Demonstrate constructive and destructive interference using pulses.
• Description:
Starting identical pulses from both ends simultaneously, either in or out of phase, they can be observed as they pass. For two identical pulses, move your hand rapidly down and up at the center of the machine with the two ends fixed. The two pulses created will reflect off the ends (left photograph) and interfere constructively as they cross each other on their return (right). Repeat this with one end clamped to get a phase reversal of the pulse which reflects off that end.
##### Engagement Suggestion
• This is a good opportunity to bring up one or two volunteers from the class to participate, rather than trying to reach both ends simultaneously yourself.
• Encourage the class to predict what will happen when the pulses pass each other.
##### Background
In a linear medium like this, two waves moving in opposite directions can be seen to pass through each other. The principle of superposition states that when two mechanical waves pass each other in a medium, the net displacement at any point is the sum of the individual wave displacements.
• Availability: Available
• Loc codes: Ofc

• #### G3-02: SHIVE WAVE MACHINE - SUPERPOSITION OF PULSES

Demonstrate constructive and destructive interference using pulses. Read More
• #### G3-03: SHIVE WAVE MACHINE - REFLECTION OF PULSES

Demonstrate reflection of pulses from fixed ends and free ends. Read More

• #### G3-05: SHIVE WAVE MACHINE - PARTIAL REFLECTIONS

Show that a wave will be partially reflected at a point where the impedance changes. Read More
• #### G3-06: SHIVE WAVE MACHINE - IMPEDANCE MATCHING

Show that no reflection occurs when the impedance of the load (absorber at right) matches the impedance of the wave machine. Read More
• #### G3-07: SHIVE WAVE MACHINE - TAPERED TRANSFORMER

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• #### G3-08: SHIVE WAVE MACHINE - FABREY-PEROT INTERFEROMETER

Demonstrate the mechanical analog of the optical Fabrey-Perot interferometer. Read More
• #### G3-09: SHIVE WAVE MACHINE - FREQUENCY FILTERING

Demonstrate the mechanical analog of the optical Fabrey-Perot interferometer. Read More
• #### G3-10: SHIVE WAVE MACHINE - BRANCHING

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• #### G3-11: SHIVE WAVE MACHINE - RESONANCE ABSORPTION

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• #### G3-20: WAVE APPARATUS

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• #### G3-23: TRANSVERSE WAVES ON A LONG SPRING - FREE END

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• #### G3-25: SLINKY ON LECTURE TABLE - IMPEDANCE MISMATCH

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• #### G3-26: AIR TRACK - LONGITUDINAL WAVES

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• #### G3-27: AIR TABLE - TRANSVERSE AND LONGITUDINAL WAVES

Demonstrate transverse and longitudinal waves using an air table. Read More

Shows longitudinal and transverse traveling waves & standing waves Read More
• #### G3-29: SUSPENDED SLINKY - PORTABLE

Show longitudinal and transverse traveling waves and standing waves. Read More
• #### G3-31: Spring and Horns

Show sound waves from a mechanical wave Read More
• #### G3-41: WAVE MODELS - PROJECTION

Demonstrate standing waves, travelling waves, and superposition of waves. Read More
• #### G3-42: TORSIONAL WAVES

Demonstrate wave phenomena such as traveling waves, standing waves, and reflection of waves Read More
• #### G3-43 WHIP

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• #### G3-45: RESONANCE OF WIRES

Show standing waves in heavy wires fixed at one end. Read More
• #### G3-46: STANDING WAVES IN A WIRE LOOP

Illustrate circular standing waves; to use as a model of stationary states in atoms corresponding to standing waves of electrons Read More
• #### G3-51 ROPE WAVE GENERATOR - FREQUENCY VS. WAVELENGTH

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• #### G3-52: ROPE WAVE GENERATOR - ROPE TENSION VS WAVELENGTH

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• #### G3-53 STANDING WAVES IN A STRING

Demonstrates standing waves on a thin string Read More
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