How Do Voltage and Current Behave in Series and Parallel Light Bulb Circuits?

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In a parallel circuit with two light bulbs rated at 30W and 40W, each bulb experiences the same voltage of 120V, resulting in different currents based on their power ratings. The resistance for each bulb can be calculated using the formula R = V^2 / P, yielding specific values for both bulbs. In contrast, when connected in series, the total voltage of 120V is divided between the bulbs, leading to a shared current throughout the circuit. The voltage drop across each bulb in series is proportional to its resistance, affecting the overall brightness. Understanding these behaviors is crucial for analyzing circuit performance in different configurations.
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Homework Statement


Two Light bulbs, one rated 30W at 120V and another rated 40W at 120V are arranged in two different circuits.
a) they bulbs are connected in parallel to a 120V source

determine the resistance and current in both bulbs.

b) determine the resistance and current if they are connected in series


Homework Equations


P=IV

V=IR


The Attempt at a Solution



I took the power over the voltage to find the current and then plugged that into V=IR, but how does the voltage and current differ when it splits, or when it is in series?
 
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The load voltages for a parallel configuration is the same across each load. Each light in the parallel configuration has the same voltage.

For a series configuration the load voltages add to equal the source voltage.
 

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