Ans. RESISTORS CONNECTED IN SERIES
In series combination, resistors are connected end to end and electric current has a single path to flow through the circuit. This, means that the current 'passing through each resistor is the same.
The total voltage in a series circuit divides among the individual resistors so the sum of the voltage combination
across the resistance of each individual resistor is equal
to the toiai voltage supplied by the source (battery). Thus, we can write as
V = V1+V2 + V3 ...... (i)
where V is the voltage across the battery, and V^ V2, V3 are the voltages across resistors R1, R2 and R3 respectively. If I is the current passing through each resistor, then, Eq.(1) can be written as:
V = IR1 +IR2-HR3
(2) We can replace the combination of resistors with a single resistor called the equivalent resistance Re such that the same current passes through the
circuit.
From Ohm's law
V = IRe Thus Eq. (2) becomes
IRe = I(R, + R2
R3)
(3)
Thus the equivalent resistance of a series combination is equal to the sum of the individual resistances of the combination.
If resistances R1t R2, R3, ..., Rn are connected in series, then the equivalent resistance of the combination will be given by
Re = R1 + R2 + R3-H...+Rn '