User:Iain sci/sandbox

The connection between a.c. voltage and d.c. voltage is a simple mathematical relationship which can be shown by using a circuit with two power sources, a lamp and a light intensity meter.^[1]

The circuit for the diagram is provided here

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 V_dc = √2 × V_ac

The value of √2V_ac is known as V_rms

^ https://spark.iop.org/comparing-rms-value-and-peak-value-ac`

[1] ttps://spark.iop.org/comparing-rms-value-and-peak-value-ac`

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