Reducing voltage with two resistors

In summary, the conversation discusses how to reduce an electric potential of 6.0 V to 5.0 V in order to run certain computer chips. It suggests using two resistors in series, with one having a resistance of 330 Ohms. The conversation then provides a hint to find the resistance of the second resistor by using the concept of a voltage divider.
  • #1
banoosh
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0

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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  • #2
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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Likes banoosh
  • #3
Look up: voltage divider
 
  • #4
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.
 
  • #5
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
 

1. How do two resistors reduce voltage?

Two resistors can be connected in a series or parallel circuit to reduce the voltage. In a series circuit, the voltage is divided between the resistors, reducing the overall voltage. In a parallel circuit, the resistors provide multiple pathways for the current to flow, resulting in a lower voltage across each resistor.

2. What is the formula for calculating the voltage drop across two resistors?

The formula for calculating the voltage drop across two resistors in series is V1 + V2 = Vtotal, where V1 and V2 are the voltages across each resistor and Vtotal is the total voltage. In a parallel circuit, the formula is 1/Vtotal = 1/V1 + 1/V2, where V1 and V2 are the voltages across each resistor and Vtotal is the total voltage.

3. What is the purpose of reducing voltage with two resistors?

The purpose of reducing voltage with two resistors is to control the flow of electricity in a circuit. By reducing the voltage, the current can be regulated and the components in the circuit can be protected from damage. Additionally, reducing voltage can also be used to increase the efficiency of a circuit.

4. How do you choose the appropriate resistors for reducing voltage?

The appropriate resistors for reducing voltage depend on the desired voltage drop and the current in the circuit. The resistors should have a value that is significantly higher than the load in order to prevent too much current from flowing. It is also important to consider the power rating of the resistors to ensure they do not overheat.

5. Can reducing voltage with two resistors affect the overall performance of a circuit?

Yes, reducing voltage with two resistors can affect the overall performance of a circuit. It can cause a decrease in power and efficiency, as well as introduce additional resistance and heat into the circuit. It is important to carefully select and place the resistors in order to minimize any negative impact on the circuit's performance.

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