Reducing voltage with two resistors

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    Resistors Voltage
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Homework Help Overview

The problem involves determining the resistance needed for a second resistor in a series circuit with a 6.0 V battery, where a 5.0 V potential is required for a computer chip. The original poster provides one resistor's value and seeks to find the other resistor's value to achieve the desired voltage across one of them.

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • The original poster attempts to calculate the current and equivalent resistance but expresses confusion about how to relate these to the voltage requirement. Some participants suggest visualizing the circuit differently, considering the computer chip's placement and its current draw.

Discussion Status

Participants are exploring different interpretations of the circuit setup and discussing assumptions about the current drawn by the computer chip. There is no explicit consensus yet, but some guidance on visualizing the circuit has been provided.

Contextual Notes

The original poster notes confusion regarding the wording of the question and assumptions about the chip's current draw, which may affect the analysis.

banoosh
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Homework Statement



An electric potential of 5.0 V is required to run certain computer chips. A 6.0 V battery may be used to do this but it must be connect to two resistors in series. Supposing one has a resistance of 330 Ohms what should the other be? (The computer chip will be driven by the voltage across only one of the two resistors.)

Homework Equations


Req= R1+R2+...
Voltage=current x req

The Attempt at a Solution


I realize that equivalent resistance for series circuits just involves simple addition, but I don't know how to tie that in with voltage. Initially I tried solving for current (330 ohms(I)= 6V) and got .018 Amperes. plugged that into 5 volts to find the req (5v= R(.018)) and came out with 277. subtracted that from 330 and got 53 which is wrong. ?
 
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The question is awkwardly worded, but the key is in the parentheses at the end. Picture the two resistors in series. Picture the computer chip in parallel with the second resistor. Finally assume that the computer chip draws very little current compared to what flows through the two resistors. (A terrible assumption if this were the real world). Can you find a value for the second resistor such that the voltage drop across the second resistor is 5 volts?
 
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Look up: voltage divider
 
Moderator note: I've re-named your thread to: Reducing voltage with two resistors. Thread titles must be descriptive of the question or problem being asked, not a plea for help. Refer to the pinned thread: Guidelines for students and helpers pinned at the top of the thread list for more information.
 
Cutter Ketch said:
The question is awkwardly worded, but the key is in the parentheses at the end. Picture the two resistors in series. Picture the computer chip in parallel with the second resistor. Finally assume that the computer chip draws very little current compared to what flows through the two resistors. (A terrible assumption if this were the real world). Can you find a value for the second resistor such that the voltage drop across the second resistor is 5 volts?
thanks! the wording of the question did confuse me, so much appreciated
 

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