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how to solve equation and mark value on its graph?
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Let's say r = 200 ohm, and c = 200 microF
I have the following equation
Vc = V*(1-exp(-t./(R*C)));
and I need to solve it to get the value of t when v = 8 volts.
2 个评论
Image Analyst
2020-12-21
编辑:Image Analyst
2020-12-21
What is v? Or did you mean V (MATLAB is case sensitive) or Vc?
And what is V?
Is this homework:
If I guess V = 10, I get this:
R = 200 % ohm and
C = 200 % microF
C = C * 1e-6 % Farads
V = 10; % Volts Guessing here!
% I have the following equation
t = linspace(0, .6, 1000);
Vc = V * (1 - exp(-t ./ (R * C)))
plot(t, Vc, 'b-', 'lineWidth', 2);
grid on;
xlabel('t', 'FontSize', 20);
ylabel('Vc', 'FontSize', 20);
yline(8, 'Color', 'r', 'LineWidth', 2);
% and i need to solve it to get the vakue of t when v = 8 v
![](https://www.mathworks.com/matlabcentral/answers/uploaded_files/467040/image.png)
回答(1 个)
KSSV
2020-12-21
syms Vc V t R C
eqn = Vc - V * (1 - exp(-t ./ (R * C)))==0 ;
s = solve(eqn,t)
The above is the formula from the equation to solve for t. Substitute your values and get the values of t.
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