Consider the circuit in the attachment(adsbygoogle = window.adsbygoogle || []).push({});

I know that the current is the same in a series circuit and voltage is divided at the 3 resistors. And resistance is added.

R = R1 + R2 + R3 = 100 + 200 + 300 = 600 Ω.

V = IR, 12 = I * 600, I = 0.02 amps = current flowing through the circuit.

V1 (voltage @ R1) = IR1 = .02 * 100 = 2 v

V2 (voltage @ R2) = IR2 = .02 * 200 = 4 v

V3 (voltage @ R3) = IR3 = .02 * 300 = 6 v

V1 + V2 + V3 = 2 + 4 + 6 = 12v same as the supplied voltage

If I measure the current at point A will it 0.02 A? I mean at A it has not passed through the resistance. So shouldn’t it be greater than 0.02 A and when meeting the resistance it reduces to 0.02A?

Assuming that the LED requires minimum 0.01 amps to glow, out of the 0.02 amps flowing in the circuit will the LED take only 0.01 amps and leave the remaining? If so after passing through the LED the current that flows to the -ve terminal is only 0.01?

When someone says “resistance is a circuit” does it mean that the resistance is there from the beginning of the circuit i.e. from the +ve terminal all the way to through the circuit to –ve terminal? If so how come? In the above case assuming I connect the +ve terminal of the 12V battery to first resistor by a piece of wire, shouldn’t current between +ve terminal and first resistor be greater than the current at the resistor?

Why is their voltage drop and not current reduction? How can voltage drop? Current is the flow of electrons right? When meeting with resistance isn’t the flow of electrons that is being restricted? And not the voltage which is the ‘force’ that ‘pushes’ the electrons?

What exactly happens when the flow of electrons meet with a resistor? Will some electrons be left at the resistor i.e. blocked by resistors and others carry on? For example current before meeting resistance is 10amps and after meeting a resistance reduces to 8amps. So 2amps are left at the resistance in other words electrons carrying the 2 amps are left at the resistance right? What happens to those electrons and current left at resistance?

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# Voltage and current in a series circuit

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