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Draft:AC-DC light experiment

AC-DC light experiment is a simple mathematical experiment to show the connection between AC and DC voltage which can be shown by using a circuit with two different power sources (ie.- AC, DC), a lamp, and a light intensity meter.[1]

Experiment

Circuit diagram

A DC voltage is selected and the intensity of light is recorded. The switch is then shifted to connect the AC supply which is adjusted until the same brightness is achieved with the bulb. The peak value of this AC voltage is recorded.

After a series of voltage pairs have been determined a graph can be produced and the gradient of the graph shows the relationship between the AC voltage and the DC volage.

A graph showing a directly proportional relationship between AC peak voltage and dc voltage for the same power
AC peak voltage versus DC voltage graph

The relationship is found to be Vac = √2 × Vdc

The value of Vac/√2 is known as Vrms. It is the quoted value of AC sources such as mains electricity[2].

References

  1. ^ "Comparing RMS value and peak value of AC | IOPSpark".
  2. ^ "Cyberphysics - UK mains voltage".
Quelle: https://en.wikipedia.org/wiki/Draft:AC-DC_light_experiment