How to use inductors and capacitors to increase power through resistor?

In summary, adding capacitors and inductors to a circuit containing a 15 volt battery and a resistor with a power rating of 1/4 watt can allow the resistor's power rating to be exceeded. In an AC circuit, the voltage across the resistor can be higher than the voltage source, especially near resonance. By connecting the resistor in parallel with a reactive element and finding the right conditions, the power of the circuit can exceed the nominal power rating of the resistor. For example, when a 2 μF capacitor and a 0.5 H inductor are connected in series with the resistor and a 15 V source with an angular frequency of ω=1000 1/s, the power can be determined to
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i'm given a circuit that contains a 15 volt battery and a resistor that has a power rating of 1/4 watt and a resistance that must be greater than 1 kohm. I'm told that no matter how i set it up, i cannot exceed the 1/4 watt power rating of the resistor. this makes sense. i work out the max power using P = IV and get 0.225 watts. however, the problem then asks me to add capacitors and inductors to the circuit such that the resistor's power rating is exceeded. how would i use capacitors and inductors to do this?

i don't really want an explicit answer but would really appreciate help with the general idea of how this could be done. we haven't covered this but it's on the hw.
 
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In an AC circuit, the voltage across the resistor can exceed that of the voltage source. Remember that the AC voltage near resonance can be very high with respect to the source voltage. If you have the resistor connected parallel to a reactive element, the voltage across it can be higher than the source voltage or the allowed voltage.

Try a circuit with an inductor in series with the resistor connected parallel with a capacitor. Find the condition needed that the power of the circuit exceed the nominal power rating of the resistor.

As an example, determine the power when the angular frequency of the 15 V source is ω=1000 1/s and a 2 μF capacitor is connected parallel to the 1kΩ resistor, and they together are in series with a 0.5 H inductor.

ehild
 
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1. How do inductors and capacitors increase power through a resistor?

Inductors and capacitors can increase power through a resistor by storing energy in their respective magnetic and electric fields. When the resistor is in a circuit with these components, the stored energy is released in bursts, increasing the overall power delivered to the circuit.

2. Can I use any inductor and capacitor to increase power through a resistor?

No, the choice of inductor and capacitor is crucial in increasing power through a resistor. The values of these components must be carefully selected to match the frequency of the circuit and the desired power output.

3. How do I calculate the values of inductors and capacitors needed to increase power through a resistor?

The values of inductors and capacitors can be calculated using the following formulas: for inductors, L = R/(2πf), where R is the resistance of the circuit and f is the frequency; for capacitors, C = 1/(2πfR), where R is the resistance and f is the frequency. These calculations ensure that the components are properly matched to the circuit.

4. Can I use inductors and capacitors to increase power through a resistor in any type of circuit?

Inductors and capacitors can be used to increase power through a resistor in various types of circuits, such as AC circuits, DC circuits, and oscillating circuits. However, the values of the components may vary depending on the type of circuit and the desired power output.

5. Are there any risks or limitations in using inductors and capacitors to increase power through a resistor?

Yes, there are some risks and limitations to consider when using inductors and capacitors to increase power through a resistor. These components can introduce noise and instability in the circuit, and their size and cost may limit their use in certain applications. It is important to carefully design and test the circuit to ensure safe and effective use of these components.

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