# RLC problem

#### Furki

Joined Mar 1, 2009
10

#### Furki

Joined Mar 1, 2009
10
Sorry for being vague but

What is the equation of the curve that joins the peaks of this wave(the one shown in the picture)?

#### mik3

Joined Feb 4, 2008
4,846
The equation is:

y=Aexp(-bx)

Find the right values for A and b.

#### mik3

Joined Feb 4, 2008
4,846
From the graph and the equation you have given it has to be:

y=250*exp(-62.5t)

#### Furki

Joined Mar 1, 2009
10
Putting t = 26.4ms in y=250*exp(-62.5t) gives 48, it should give 59.2V according to the graph.

btw,
R = 500 ohms, L = 4H, C = 1 uF

#### mik3

Joined Feb 4, 2008
4,846
Then use a point from the graph to calculate A.

#### alwayslearning

Joined Feb 27, 2008
22
You say your plot is marked at 2.5 Volts? It is actually marked at 59.2 Volts.
If you desire to know the value of (t) at 2.5 Volts then specify at which time?

Please specify the initial conditions-I took a guess as -->source is zero, i(0)=0.5 Amps and Vc(0)=377 Volts? Or
di(0)/dt could also have been given instead as 94.24 assumming your A1, A2 are correct?

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