Page 27 - CHAPTER-1 (Electricity)

CHAPTER 1

ELECTRICITY

K. The Resistance of a System of Resistors

• Two or more resistors can be connected with each other by

different combinational methods in order to achieve the desired

equivalent resistance in a particular circuit.

• There are a couple of basic methods of joining the resistors

together, which are as given below:

(i) Resistors in Series

• When two resistors or more than two are connected end to end to

each other, then they are connected in series.

• The following figure shows the connection of resistors in series.

Fig 10:

An applied potential produces current in the resistors and R , R and
1
2
R causing a potential drop V ,V and V respectively, through each
1
2
3
3
resistor.
Total potential, V=V +V +V
2
3
1
By Ohm’s law, V =IR , V =IR and V =IR
3
3
2
1
2
1
Thus, V=V +V +V =IR +IR +IR
1
2
1
2
3
3
⇒V=I(R +R +R )
1
3
2

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