Concept explainers
(a)
The actual power delivered to the vacuum cleaner.
(a)
Answer to Problem 42P
The actual power delivered to the vacuum cleaner is
Explanation of Solution
Write the expression for the power delivered to the vacuum cleaner.
Here,
Write the expression for the
Here,
Use equation (II) in (I) to solve for
Use equation (III) to solve for
Write the expression for the total resistance in the circuit.
Here,
Write the expression for current throughout the circuit.
Use equation (II) to solve for
Write the expression for the power of the cleaner.
Here,
Use equation (VII) in (VIII) to solve for
Use equation (V) in (VI) to solve for
Use equation (X) in (IX) to solve for
Conclusion:
Substitute
Substitute
Substitute
Therefore, the actual power delivered to the vacuum cleaner is
(b)
The required diameter of the copper conductors for a power of at least
(b)
Answer to Problem 42P
The required diameter of the copper conductors for a power of at least
Explanation of Solution
Use equation (XI) to solve for
Write the expression for the
Here,
Write the expression for
Here,
Use equation (XIV) in (XIII) to solve for
Conclusion:
Substitute
Substitute
Therefore, the required diameter of the copper conductors for a power of at least
(c)
The required diameter of the copper conductors for a power of at least
(c)
Answer to Problem 42P
The required diameter of the copper conductors for a power of at least
Explanation of Solution
Use equation (XII) to solve for
Use equation (XV) to solve for
Conclusion:
Substitute
Substitute
Therefore, the required diameter of the copper conductors for a power of at least
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Chapter 21 Solutions
Principles of Physics: A Calculus-Based Text
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- The values of the components in a simple series RC circuit containing a switch (Fig. P21.53) are C = 1.00 F, R = 2.00 106 , and = 10.0 V. At the instant 10.0 s after the switch is closed, calculate (a) the charge on the capacitor, (b) the current in the resistor, (c) the rate at which energy is being stored in the capacitor, and (d) the rate at which energy is being delivered by the battery.arrow_forwardWhen the switch is open in Figure 18.8, power Po is delivered to the resistor R1. When the switch is closed, which of the following is true about the power Pc delivered to R1? (Neglect the internal resistance of the battery.) (a) Pc Po (b) Pc = Po (c) Pc Po Figure 18.8 (Quick Quizzes 18.5 and 18.6)arrow_forwardThe timing device in an automobile's intermittent wiper system is based on an RC rime constant and utilizes a 0.500F capacitor and a variable resistor. Over whatrange must R be made to vary to achieve time constants from 2.00 to 15.0 s?arrow_forward
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