Acoustic source to demonstrate the Doppler effect.
Integrated loudspeaker, 2 sinus tones with different frequencies selectable (audible and ultrasound), volume tunable.

Benefits

• Compact, with integrated hook, thus can be mounted on a cart or spring
• Tunable volume
• 2 sinus tones with different frequencies selectable: audible for demonstration of the Doppler effect, and ultrasound for quantitative measurements of the frequency shift

Equipment and Technical Data

• Selectable frequencies: 4,6 kHz (audible) und 19 kHz (ultrasound)
• Volume tunable
• Power supply: Monobloc battery 9 V
• Dimensions: (90 x 65 x 28) mm
• Weight (incl. battery): 115 g

Glass tube, can be used in acoustics to measure resonance and standing waves

Benefits

• Transparent
• Due to the dimensions, standing waves can be measured with a microphone in the inside of the tube

Equipment and Technical Data

• Material: Glass, transparent
• Diameter d(outside) = 44 mm
• Wall thickness app. 2 mm
• Length l = 340 mm

Part of student monochord kit 13289-15

Monochord kit for student experiments,e.g. frequency, amplitude, musical scale and intervals.

Equipment and Technical Data

Kit consisting of:

• Interval plate with graduation
• Metal angle bracket
• Nylon string
• Wooden wedge

To record the oscillation of a tuning fork on a piece of paper. The tuning fork has a frequency of about 20 Hz and oscillates visibly.

Benefits

The oscillations can easily be recorded on a piece of paper – no further preparations needed. The clamp for the pen measures 1 cm in diameter, which allows to use also markers, e.g. to record the pattern on a overhead transparancy for demonstration purposes.

Equipment and technical data

• Frequency app. 20 Hz
• Clamp for pen: diameter 1 cm
• Complete with permanent marker

Simply take it out of the storage cupboard, fill with water and start!

New edition: Even easier in handling and advanced functionality – better results in less time! Furthermore: Almost soundless operation!

The ripple tank is a convenient and effective compact device for demonstration or laboratory which allows a clear but quantitative access to wave mechanics. The frequency range from 5 up to 60 Hz covers all experiments, for school and university.

It is possible to connect an external vibration generator to demonstrate interference phenomena or the Doppler effect.

The following phenomena can be observed:

• Reflection
• Dispersion
• Refraction
• Interference
• Diffraction
• Doppler effect

Benefits

• Reflection-free basin on adjustable feet
• 3-point adjustment
• Amplitude and frequency variable excitation dipper system
• Almost soundless operation
• Stroboscope for synchronous and “slow-motion” projection of waves
• Simultaneous LED display of: frequency, amplitude, phase shift and type of illumination
• Control of all parameters takes place via the keypad located on top
• Projection on transparent drwaing table for distortion-free image of the wave pattern
• Green LED for brilliant pictures
• A simple display of the wave pattern is easily possible by placement of a sheet of paper

Equipment and Technical Data

• Complete set for experiments with the ripple tank
• Ripple tank basic unit
• Power supply
• Water tray
• Drawing table
• Excitation dippers: single, double and plane wave dippers, exciter system with up to 10 dippers
• Different barriers (10 mm, 30 mm, 2 x 71 mm, 190 mm)
• Concave and convex reflector
• 1 set of refraction objects
• Spray bottle 500 ml
• Illumination technique: Permanent or stroboscope
• Frequency: 5 – 60 Hz for all required topics in school and university
• Vibration generator amplitude: 1…4
• Stroboscope frequency (Delta f): -2,5…2,5 Hz
• Phase difference: 0…360°
• Line voltage: 110…240 V
• Mains frequency: 50/60 Hz
• LED luminous flux, max.: 285 lm
• Dimensions (mm): 300 x 370 x 330 (W x L x H)
• Weight: approx. 5,7 kg

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