Finding Maximum Voltage of Resistors

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SUMMARY

The maximum voltage that can be applied across a network of resistors consisting of a 2.44-kΩ and a 4.92-kΩ resistor in parallel, combined in series with a 1.12-kΩ resistor, is calculated using the formula P=V^2/Req. The equivalent resistance (Req) is determined to be approximately 2751.09 Ohms. The correct maximum voltage, after resolving calculation errors, is approximately 37.09 V. This voltage is derived from the power rating of 1/2 W for each resistor, confirming that the voltage across parallel resistors remains constant.

PREREQUISITES
  • Understanding of Ohm's Law (V=IR)
  • Knowledge of resistor combinations (series and parallel)
  • Familiarity with power calculations (P=V^2/R)
  • Ability to convert between kilo-ohms and ohms
NEXT STEPS
  • Study the principles of series and parallel resistor circuits
  • Learn about power ratings and their implications in circuit design
  • Explore advanced resistor network analysis techniques
  • Investigate the effects of resistor tolerances on circuit performance
USEFUL FOR

Students in electrical engineering, hobbyists working on circuit design, and anyone needing to calculate maximum voltage in resistor networks.

Angie K.
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Homework Statement



A 2.44-kΩ and a 4.92-kΩ resistor are connected in parallel; this combination is connected in series with a 1.12-kΩ resistor. If each resistor is rated at 1/2 W, what is the maximum voltage that can be applied across the whole network?

Homework Equations


P=V^2/Req
V=I*R

The Attempt at a Solution


I solved for the equivalent resistance.
I converted the kΩ to Ω and used the equation for parallel resistors
1/R1,R2 = (1/R1)+(1/R2) = 1/2440 + 1/4920 = 6.1308E-4
R1,2 = 1/6.1308E-4 = 1631.086957 Ohms
then R123 = R1,2+R3 = 1631.086957+1120 = 2751.086957 Ohms
Then I used P=V^2/Req
1/2=V^2/2751.086957
V=23.6643 V (which should be the maximum voltage since parallel resistors have the same voltage throughout)
But it's wrong and I'm not sure where I messed up?
 
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Recheck your final calculation. I get an answer of 37.09 using 1/2 = V^2/2751.086957.
 
Oh that was a calculation error that I made, say it is 37.0883 V but that isn't the right answer. Am I missing some sort of equation for the maximum voltage once I figure out the V from P=V^2/R ?
 

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