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Science-Related Homework Help Physics Topic started by: folasade21 on Mar 4, 2012



Title: Resistance, ohm's law and i vs V curves
Post by: folasade21 on Mar 4, 2012
1) Consider two circuits, both being connected to a constant 3-volt source. Circuit A has two light bulbs connected in series and circuit B has the same two light bulbs connected in parallel.

a) Describe the relative brightness of the bulbs in one circuit in comparison to the other. Explain your answer using circuit analysis.

b)Compare the power delivered to circuit A with that delivered to circuit B.


Title: Re: Resistance, ohm's law and i vs V curves
Post by: marybud4 on Mar 4, 2012
a) The lamps in parallel will be brighter because each one has 3V across it, rather than only 1.5V apiece when in series.

b) This may be a trick question because incandescent lamps are HIGHLY nonlinear in their power consumption. But assuming that they simply operate as resistors R, the power used by the pair of lamps in each case is:

Parallel: (2)(3^2)/R Watts
Series: (2)(1.5^2)/R Watts

Dividing: Parallel/Series = 4