Page 29 - CHAPTER-1 (Electricity)

CHAPTER 1

ELECTRICITY

Example 9:

Three resistors of 5Ω, 10Ω and 15Ω are connected in series with a 12V

power supply. Calculate their combined resistance, the current that

flows in the circuit and in each resistor and the potential difference

across each resistor.

Solution:

Given, R =5Ω, R =10Ω and R =15Ω, V=12V, R= ?, I= ? and V ,V and
2
2
1
1
3
V = ?
3

+ -

Fig 11:

According to question, the three resistors are connected in series

combination, then equivalent resistance,

R=R +R +R =5+10+15=30Ω
2
3
1
∴ The current flowing through the circuit ( )

Potential of power supply (V)
=
Total Resistance of the circuit (R)

12 2
= = =0.4A
30 5

In series combination, the current flowing through each resistor is

equal to the total current flowing through the circuit.

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