(a)
Find the current through the emf device and each resistor in circuit 1.
(a)
Answer to Problem 39PQ
The current through the Emf device and each resistor in circuit 1 is
Explanation of Solution
According to Kirchhoff’s junction rule, in any junction, the sum of the all the currents entering the junction equals the sum of all the currents exiting the junction.
Redraw the circuit 1 and labeled it as given below
In parallel circuit, voltage across all three resistors is same that means potential difference between node A and node B is same (
According to Ohm’s law,
Here,
Rearrange the equation (I) in terms of total current
Write the expression for equivalent resistance as.
Rearrange the above expression.
Write the expression for current
Here,
Write the expression for current
Here,
Write the expression for current
Here,
Conclusion:
Substitute
Substitute
Substitute
Thus, the current in circuit 1 is
Substitute
Substitute
Substitute
Thus, the current through the Emf device and each resistor in circuit 1 is
(b)
Find the current through the emf device and each resistor in circuit 2 refer to figure P29.28.
(b)
Answer to Problem 39PQ
The current through the Emf device and each resistor in circuit 2 is
Explanation of Solution
According to Kirchhoff’s junction rule, in any junction, the sum of the all the currents entering the junction equals the sum of all the currents exiting the junction.
Redraw the circuit 2 and labeled it as given below.
In parallel circuit 2, voltage across all three resistors is same that means potential difference between node a and node b, node c & node d and node e & node f are same
Write the expression for current
Here,
Write the expression for current
Here,
Write the expression for current
Here,
Conclusion:
Substitute
Substitute
Substitute
Thus, the current in circuit 1 is
Substitute
Substitute
Substitute
Thus, the current for the given circuit resistance is
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Chapter 29 Solutions
Student Solutions Manual For Katz's Physics For Scientists And Engineers: Foundations And Connections, Volume 1
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