Coupled pendula with Cobra SMARTsenseexpert version
Principle
Two equal gravity pendula with a particular characteristic frequency are coupled by a “soft” spiral spring. The amplitudes of both pendula are recorded as a function of time for various vibrational modes and different coupling factors. The coupling factors are determined by different methods.
Benefits
- Large and sturdy set-up suitable for demonstration and lab courses as well
- Live data-logging system to measure the oscillations of both pendula at once
USB charger for Cobra4 Mobile-Link 2 and Wireless/USB-Link
Measuring tape, l = 2 m
Cobra4 Wireless/USB-Link incl. USB cable
Cobra4 Sensor-Unit Electricity, current ± 6A / voltage ± 30V
Electrol.capacitor10microF/35V,G1
Support rod, stainless steel, 500 mm
Support rod, stainless steel, 750 mm
Rod with hook
Weight holder,
Slotted weight, black, 10 g
Helical spring, 3 N/m
Pendulum with recorder connection
Connecting cord, 32 A, 1000 mm, red
Connecting cord, 32 A, 1000 mm, blue
PHYWE power supply, 230 V, DC: 0…12 V, 2 A / AC: 6 V, 12 V, 5 A
Software Cobra4 – multi-user licence
Right angle clamp expert
Bench clamp expert
Tasks
- To determine the spring constant of the coupling spring.
- To determine and to adjust the characteristic frequencies of the uncoupled pendula.
- To determine the coupling factors for various coupling-lengths using a) the apparatus constant, b) the angular frequencies for “inphase”and “in opposite phase” vibration, c) the angular frequencies of the beatmode.
- To check the linear relation between the square of the coupling lengths and a) the particular frequencies of the beat mode, b) the square of the frequency for “inopposite phase” vibration.
- To determine the pendulum’s characteristic frequency from the vibrational modes with coupling and to compare this with the characteristic frequency of the uncoupled pendula.
What you can learn about
- Spiral spring
- Gravity pendulum
- Spring constant
- Torsional vibration
- Torque
- Beat
- Angular velocity
- Angular acceleration
- Characteristic frequency