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Electricity and MagnetismI Voltages
in Series Circuits
Consider the simple series circuit above. Energy lost by each Coulomb of charge moving from A to B is V_{1}. Energy lost by each Coulomb of charge moving from B to C is V_{2}. Energy lost by each Coulomb of charge moving from C to D is V_{3}. Obviously the total amount of energy lost by each Coulomb of charge moving from A to D must be V_{1} + V_{2} + V_{3} (= V). Conclusion The total voltage across components connected in series is the sum of the voltages across each component. Note that the validity of this statement does not depend on what the components are. Voltage
across Components in Parallel
Conclusion Components connected in parallel with each other all have the same voltage. Again, this does not depend on what the components are. 
