Draw the magnitude and phase angle of a voltage in this AC circuit

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SUMMARY

This discussion focuses on calculating the magnitude and phase angle of voltage in an AC circuit using MATLAB. The user shared their MATLAB code, which converts voltage from polar to rectangular form and applies voltage division rules (VDR) to analyze the circuit's behavior. Key parameters include resistance (R = 10 ohms), inductance (L = 10 mH), and capacitance (C = 50 µF). The results demonstrate a 90-degree phase difference at the resonant frequency and a drop in voltage across the capacitor at higher frequencies.

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Fatima Hasan
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Homework Statement
Consider the simple ac circuit of figure 1(b). The frequency of the AC source varies between 100 Hz to 500 Hz. Draw the magnitude and phase angle of the voltage across the capacitor. Try to increase the frequency by step of 5 Hz.
The circuit is attached below.
Relevant Equations
-
My solution is attached below.
I am not sure if my answer is correct or not , I want to confirm it.
 

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Fatima Hasan said:
if my answer is correct or not
From the code ?

244974


it seems strange to me that L and C are treated similarly ...

PS: PF has
Matlab:
 ... your code here ...  [\CODE] tags that present it much mure usefully:

[code=matlab] for i = 1:((500-100)/5 + 1) 
     w(i) = ...
 
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BvU said:
[\CODE] tags that present it much mure usefully:
Thank you !

C should be = 1/(Xc*j*w(i))
I resolve it again and here's what I got :
Matlab:
clc;
clear all;
v=100*(sind(0)*j+cosd(0)); %convert from polar to rectangular form
r=10;
xl=10*10^(-3);
xc=50*10^(-6);
f=100:5:500;
for i=1:((500-100)/5+1)
    w(i)=f(i)*2*pi;
    l(i)=j*w(i)*xl;
    c(i)=1/(xc*j*w(i));
    vc(i)=v*c(i)/(c(i)+l(i)+r); %apply VDR
end
figure(1)
subplot (2,1,1) , plot(f,abs(vc))
subplot (2,1,2) , plot(f,rad2deg(angle(vc)))
 

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Looks a lot better now !
Checks are 90 degree phase difference at ##\ 2\pi f = {1\over \sqrt{LC}}\ ##
and V(C) dropping off with ##1/\omega^2\ ## at higher frequencies.
 
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