Max Power Dissipated in RLC circuit

Click For Summary
SUMMARY

The discussion focuses on calculating the maximum power dissipated in an RLC circuit consisting of a 500-ohm resistor, a 0.4 mH inductor, and two 50 pF capacitors in parallel, powered by a 1 V alternating emf. The maximum power dissipated by the resistor is defined as Pmax = (Ipeak)² * R, while for the entire circuit, it is Pmax = (Irms)(Vrms)cos(phi). The resonant frequency is determined using the formula frequency = 1/Sqrt(LC). The quality factor (Q) of the resonator is crucial for understanding the frequencies at which the maximum power is half its value.

PREREQUISITES
  • Understanding of RLC circuit components and configurations
  • Knowledge of AC circuit analysis techniques
  • Familiarity with power calculations in electrical circuits
  • Concept of resonant frequency and quality factor (Q)
NEXT STEPS
  • Calculate the impedance (Z) of the RLC circuit at resonance
  • Explore the derivation of average power in AC circuits
  • Study the impact of quality factor (Q) on circuit performance
  • Investigate the relationship between frequency and power dissipation in RLC circuits
USEFUL FOR

Electrical engineering students, circuit designers, and anyone involved in analyzing or designing RLC circuits for power efficiency and performance optimization.

pynergee
Messages
7
Reaction score
0

Homework Statement


For this sample exam, we are given an RLC circuit, with an alternative emf of 1 V, connected all in series with a 500 ohm resistor, a .4 mH inductor, and two capacitors in parallel of 50 pF each.
It asks for the "maximum power dissipated by the resistance" and at what frequencies w would the max power be half as large.

Homework Equations


I am not sure if the question is asking for the power dissipated by resistor, or the entire circuit.
If it were just the resistor, Pmax = (Ipeak)squared * R
But if it were the entire circuit, Pmax = (Irms)(Vrms)cos(phi)
where, (Irms) = (Vpeak/Z)/Sqrt(2) and (Vrms) = (Vpeak)/Sqrt(2) and cos(phi) = (R/Z) I believe.
The frequency = 1/Sqrt(LC)

The Attempt at a Solution


I know how to find the Pmax, but I just need to know for that, if it is the resistor or the entire circuit its asking for.
However for the frequency, I am somewhat stuck.
Would I try to use the derivation of <P> = <[(Ipeak)sin(wt-phi)][(Vpeak)sin(wt)]?

Please help, thank you.
 
Physics news on Phys.org
Don't get hung too up on cosinusoids, but look at the impedance of your resonant circuit. What is it exactly on resonance? This will answer the first question. It should show you the way to the second question, too. As a practical matter, the quality factor or Q of the resonator is related to the frequencies you'll find for part two.
 

Similar threads

  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 21 ·
Replies
21
Views
1K
  • · Replies 1 ·
Replies
1
Views
2K
Replies
4
Views
2K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 3 ·
Replies
3
Views
1K
Replies
22
Views
4K
Replies
6
Views
1K
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 6 ·
Replies
6
Views
2K