Phase velocity of standing waves with Cobra SMARTsense

Principle

A linearly polarized standing transverse wave is generated on a rubber band with a square cross-section by means of a vibration generator. The wavelength is determined as a function of the excitation frequency. Then the phase velocity of the cable wave is changed by changing the tensile stress. The relationship between the phase velocity of the rope and the tension on the rope is investigated. With the help of a stroboscope the standing wave can be displayed even more impressively.

Tasks

1. At constant tensile stress the frequency depends on the wavelength λ of the wave propagating on the rope. The frequency is calculated as a function of 1 / λ. From this diagram the phase velocity c can be determined. 
2. The phase velocity c of the rope wave, which depends on the tensile stress of the rope, is to be measured. The phase velocity is displayed as a function of the tensile stress

Learning objectives

• Wavelength
• Phase Speed
• Group speed
• wave equation
• Harmonic

Benefits

• Very illustrative way to watch the propagation of waves including damping, couping, standing waves and many more
• Slow propagation speed allows an excellent observation in particular with a stroboscope