
Concept explainers
(a)
Find the value of
(a)

Answer to Problem 28E
At
Explanation of Solution
Formula used:
The expression for the current flowing through the resistor is as follows.
Here,
Calculation:
The redrawn circuit diagram is given in Figure 1.
Refer to the redrawn Figure 1.
The given circuit inductor is connected for 6 years prior to being flipped open at
Apply KCL at node 1.
Here,
Substitute
Rearrange the above equation for
The voltage across
Substitute
Conclusion:
Thus, at
(b)
Find the value of
(b)

Answer to Problem 28E
At
Explanation of Solution
Calculation:
The redrawn circuit diagram is given in Figure 2.
Refer to the redrawn Figure 2.
The expression for the voltage across the
Here,
Refer to the redrawn Figure 2.
The inductor does not allow sudden change in the current.
So, the current through inductor at
Apply KVL in the right side mesh.
Here,
Substitute
Rearrange for
Substitute
Conclusion:
Thus, at
(c)
Find the value of
(c)

Answer to Problem 28E
At
Explanation of Solution
Given data:
The time is
Formula used:
The expression for the equivalent resistor connected in series is as follows.
Here,
The expression for the time constant for
Here,
The expression for the current for
Here,
Calculation:
The redrawn circuit diagram is given in Figure 3.
Refer to the redrawn Figure 3.
The simplified diagram is shown in Figure 4.
Refer to the redrawn Figure 4.
Substitute
Substitute
Substitute
Rearrange the above equation for
Substitute
Conclusion:
Thus, at
(d)
Find the value of
(d)

Answer to Problem 28E
At
Explanation of Solution
Given Data:
The time is
Calculation:
Substitute
Substitute
Rearrange the above equation for
Substitute
Conclusion:
Thus, at
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Chapter 8 Solutions
ENGINEERING CIRCUIT...(LL)>CUSTOM PKG.<
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