Concept explainers
(a)
The current and power dissipated in the circuit.
(a)
Answer to Problem 27E
The current in the circuit is
Explanation of Solution
Given that the voltage is
Write the expression for the current according to Ohm’s law.
Here,
Write the expression for power dissipated.
Here,
Conclusion:
Substitute
Substitute
Therefore, the current in the circuit is
(b)
The resistance that required to draw
(b)
Answer to Problem 27E
The resistance that required to draw
Explanation of Solution
Given that the current drawn is
Equation (I) can be solved for
Since the battery has internal resistance, the required resistance can be computed as,
Here,
Conclusion:
Substitute
Substitute
Therefore, the resistance that required to draw
(c)
The power dissipated in the motor.
(c)
Answer to Problem 27E
The power dissipated in the motor is
Explanation of Solution
Given that the current drawn by the motor is
Write the expression for the power supplied.
Here,
Conclusion:
Substitute
Therefore, the power dissipated in the motor is
(d)
The power dissipated in the battery.
(d)
Answer to Problem 27E
The power dissipated in the battery is
Explanation of Solution
Given that the internal resistance of the battery is
Equation (V) can be used to find the power dissipated in the battery, by replacing
Conclusion:
Substitute
Therefore, the power dissipated in the battery is
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Chapter 17 Solutions
General Physics, 2nd Edition
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