Question

Learning Goal: To understand the use of phasor diagrams in calculating the impedance and resonance conditions in a series L-R-C circuit. At resonance, XL = Xc. The voltage across the capacitor exactly cancels that across the i have the same amplitude. Thus, the inductor and capacitor effectively cancel out in the formu not come as a surprise that the resonant frequency equals the natural frequency of the oscilla In this problem, you will consider a series L-R-C circuit, containing a resistor of resistance R, an inductor of inductance L, and a capacitor of capacitance C, all connected in series to an AC source providing an alternating voltage V(t) = V cos(wt). (Figure 1) Part D What is the phase angle o between the voltage and the current when resonance is reached? View Available Hint(s) You may have solved a number of problems in which you had to find the effective resistance of a circuit containing multiple resistors. Finding the overall resistance of a circuit is often of practical interest. In this problem, we will start our analysis of this L-R-C circuit by finding its effective overall resistance, or impedance. The impedance Z is defined by where V and I are the amplitudes of the voltage across the entire circuit and the current, respectively. V ACOM O ? Submit Figure < 1 of 2 > Part E AC source Now imagine that the parameters R, L, w, and the amplitude of the voltage Vo are fixed but that the easiest parameters to change when "tuning" such (radio frequency) circuits in order to make them re be changed just by moving the capacitor plates closer or farther apart. Find the capacitance Co atr Express your answer in terms of L and W. elle | Co = whet Submit Previous Answers Correct When resonance is reached. X = Xc. The average power dissipated in the circuit undert

Answer 1

AT resonance

XL = Xc

XL-Xc = 0

Phi = tan^-1[(XL-Xc)/R]= tan-1(0) = 0°... answer.

Hope this helps!

Please thumbs up.