I'm having trouble understanding something in one of my text books:
Let’s have a look at the implications of each circuit configuration. Figure 3.13 shows the Conventional representation of a parallel circuit. If you assume that the resistance of the wires can be neglected, then the voltage drop across each bulb is equal to the e.m.f. of the source, the dynamo. The Current flowing from the source is divided between each bulb depending on its resistance (remember I = E/R), Removing one of the bulbs would not affect the voltage drop across the other bulb and would therefore not affect the Current in it, although the overall Current from the dynamo would drop as the demand has been reduced.
Specifically, the line about removing one of the bulbs not affecting the voltage drop. My understanding is that the sum of voltage drops in a circuit must be equal to the output of the emf, but the way I'm reading the text suggests that if you have three bulbs in a parallel circuit and you remove one of them, the voltage drop remains the same - this is what I don't understand, though. If you a lamp is removed, then that's one less lamp consuming emf. Does it not get redistributed to the other two lamps?
Likewise, the text mentions the overall current from the dynamo dropping because demand has been reduced.
My initial understanding was that current from an emf is only affected by the emf - not the demands of components further along the circuit, as in this case. What have I misunderstood?
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