iSES - Internet School Experimental System

Natural and driven oscillations

Assignment

1. Make familiar with the experiment, damped oscillations and forced oscillations of the oscillator.
2. Carry out the measurement of the damped oscillations of the oscillator. This can be done by turning off the driving force and monitoring the oscillations of free oscillations. Save your data.
3. Find out from several measurements the natural frequency of the damped oscillator
   ω_b = (ω_o² - b²)^{1/ 2}, and also the damping b (from equation (7)).
4. Carry out the measurement of the forced oscillations for the entire interval of frequencies of the driving force ω_v, save your data.
5. Plot the dependence of the amplitude ofthe driven oscillations A_v (see (Fig 6) (a) and equation (12)) on the angular frequency of the driving force ω_v. Determine the resonance frequency ω_{v, res}. Plot the graph.
6. Try to evaluate for several frequencies of the driving force ω_v the initial phase of forced oscillations φ_v (from (Fig 6) (b) and equation (13)). Plot the graph.
7. For advanced: The phenomenon of driven oscillations and resonance can be very often observed in the nature and also in the technology (in the nature, e.g. in the absorption of UV radiation on ozone molecules; in technology e.g. in resonance circuits in telecommunications). Think about the energy transferred by the driving force in the system with the oscillator. When is this energy transfer the greatest?
8. Discuss, as the future teachers, the possibiliies of remote experiments.
9. Work out a report containing the following items:
   1. Introduction to the technology of remote experiments.
   2. Physical introduction to the phenomenon observed.
   3. Description of the experiment and its arrangement, aids and the sample of real measured data.
   4. Results achieved.
   5. Discussion of the achieved results and the remote experiment.
   6. Literature