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What is meant by an 'equivalent resistor' for a group of resistors?
AThe largest individual resistor found anywhere in the group
BA single resistor with the same combined resistance as the group
CA resistor added purely to protect the circuit from overheating
DThe average of the voltage ratings of all the batteries used
Answer & Solution
Correct answer: B. A single resistor with the same combined resistance as the group
1. Replacing several resistors with one resistor is useful for simplifying circuit analysis.
2. That single replacement resistor must produce the same current as the original combination.
3. It is defined as having the same resistance as the combined resistance of the original set.
4. Simply picking the largest resistor in the group would not, in general, reproduce the same combined resistance.
_Source: OpenStax Physics (CC BY 4.0), Ch 19 "Electrical Circuits", section Resistors in Series and Equivalent Resistance_
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