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When the current passes through a series combination of resistors why is the current uniform in the circuit? Don't the resistors draw current (resistors like bulb)?
When several resistors are joined in series, the resistance of the combination Rs equals the sum of their individual resistances, R1, R2, R3, and is thus greater than any individual resistance.
We will observe that the value of the current in the ammeter is the same in the series circuit, independent of its position in the electric circuit. It means that in a series combination of resistors the current is the same in every part of the circuit or the same current flows through each resistor.
Even though a load like the filament of a bulb has resistance, it works like any other resistor in the series circuit, and the same current flows in the series connection of those resistors.
It is the heating effect, (I^2)R (where I is current and R is resistance) of the bulbs’ filament resistance, that gives visible radiation when the temperature reaches near 2700 K. For example, a 60 W bulb takes a current of 40 mA at 240 V, implying a resistance of 6000 ohms.
It might surprise you that the same bulb shows ZERO resistance when not glowing! Yes, all bulbs have zero resistance when cold & attain thousands of ohms when hot. This is due to the very high thermal coefficient of resistivity of Tungsten wire.
Every bulb type is made with differing diameters & lengths of Tungsten wire and has different resistance when hot and glowing.
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