All Problems

Electric Oscillations

Problem 4.138

A coil with inductance \(L=0.70 \mathrm{H}\) and active resistance \(r=20 \Omega\) is connected in series with an inductance-free resistance \(R\) An alternating voltage with effective value \(V=220 \mathrm{~V}\) and frequency \(\omega=314 \mathrm{~s}^{-1}\) is applied across the terminals of this circuit. At what value of the resistance \(R\) will the maximum heat power be generated in the circuit? What is it equal to?

Reveal Answer
 For R=ωL−r=0.20kΩ;Pmax⁡=V22ωL=0.11 kW\text { For } R=\omega L-r=0.20 \mathrm{k} \Omega ; \quad P_{\max }=\frac{V^{2}}{2 \omega L}=0.11 \mathrm{~kW}
Prev
Next