
Physics (5th Edition)
5th Edition
ISBN: 9780321976444
Author: James S. Walker
Publisher: PEARSON
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Textbook Question
Chapter 21, Problem 34PCE
Predict/Explain Two resistors are connected in parallel. (a) If a third resistor is now connected in parallel with the original two, does the equivalent resistance of the circuit increase, decrease, or remain the same? (b) Choose the best explanation from among the following:
- I. Adding a resistor generally tends to increase the resistance, but putting it in parallel tends to decrease the resistance; therefore the effects offset and the resistance stays the same.
- II. Adding more resistance to the circuit will increase the equivalent resistance.
- III. The third resistor gives yet another path for current to flow in the circuit, which means that the equivalent resistance is less.
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Chapter 21 Solutions
Physics (5th Edition)
Ch. 21.1 - Enhance Your Understanding 1. The following...Ch. 21.2 - Enhance Your Understanding 2. If the voltage and...Ch. 21.3 - Enhance Your Understanding 3. In the following...Ch. 21.4 - The two circuits shown in Figure 21-17 have...Ch. 21.5 - Prob. 5EYUCh. 21.6 - Do two capacitors give a larger equivalent...Ch. 21.7 - Give a symbolic expression for the current that...Ch. 21 - Your body is composed of electric charges. Does it...Ch. 21 - Suppose you charge a comb by rubbing it through...Ch. 21 - An electron moving through a wire has an average...
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