In the circuit shown, the 8-V battery is opposing the 12-V battery as they are positioned. The total voltage of the two batteries will be found by subtracting.
a. What is the current flowing around the circuit?
b. What is the voltage difference across the 20 Ω resistor?
c. What is the power delivered by the 12-V battery?
d. Is the 12-V battery discharging or charging in this arrangement?
(a)
The current flowing in the circuit.
Answer to Problem 3SP
The current through the circuit is
Explanation of Solution
Given info: The given circuit is shown below.
The two batteries in the given circuit have opposite polarity in the circuit. So the net potential difference of the circuit will be the difference of the two potential of the two batteries.
Write the formula for the net potential difference of the circuit.
Here,
The two resistance in the circuit are in series.
Write the formula for the equivalent resistance of the two resistances.
Here,
Write the formula for current.
Here,
Substitute the expression for
Substitute
Conclusion:
The current through the circuit is
(b)
The voltage difference across the
Answer to Problem 3SP
The voltage difference across the
Explanation of Solution
Given info: The given circuit is shown below.
The two batteries in the given circuit have opposite polarity in the circuit. So the net potential difference of the circuit will be the difference of the two potential of the two batteries.
Write the formula for the voltage difference across a resistor when two resistors are in series.
Here,
Substitute
Conclusion:
The voltage difference across the
(c)
The power delivered by the battery with voltage
Answer to Problem 3SP
The power delivered by the battery with voltage
Explanation of Solution
Given info: The given circuit is shown below.
Write the formula for the power delivered.
Here,
From section (a) the current in the circuit is
Substitute
Conclusion:
The power delivered by the battery with voltage
(d)
Whether the battery with voltage
Answer to Problem 3SP
The battery with voltage
Explanation of Solution
Given info: The given circuit is shown below.
The overall voltage of the circuit is
Thus the battery with voltage
Conclusion:
The battery with voltage
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Chapter 13 Solutions
Physics of Everyday Phenomena
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