Homework Help. Thevenin Equivalent and more.

Discussion in 'Homework Help' started by jd53887, Mar 9, 2010.

1. jd53887 Thread Starter New Member

Mar 9, 2010
2
0
1. Can someone guide me as to how I can build a Thevenin Equivalent model for this problem?

At the output of a DC circuit, it's 6 volts without any load attached. With a load of 1kΩ, the voltage becomes 4.

I'm asked to find the ohm and voltage of the Thevenin Equivalent.

EDITS AS I SOLVE IT:

I got the equivalent ohms by solving for Req = (Voc/Vab -1) *Rtest, which is 500ohms

I don't want to sound stupid, but is the Thevenin Equivalent voltage 6v? seems too simple.

Last edited: Mar 9, 2010
2. t_n_k AAC Fanatic!

Mar 6, 2009
5,448
783
Your solution is fine. Vth=6V works. Too simple is better than too complicated!

jd53887 likes this.
3. jd53887 Thread Starter New Member

Mar 9, 2010
2
0
problem 2:

v(t) = Vm sin (2(pi) * f * t)

Vm = x
2(pi) * f = y

waveform 1: v(t) = x sin (y * t)
waveform 2: v(t) = x sin (y * t - z)

I don't know how to solve this. I'm looking through my notes... and I could solve it without that z (just add the x together)... but I don't know what to do now. x is 20 and y is 3.14159265 and z is 1.5 if that matters.

I'm looking for the peak value of their sum and phase shift of their sum in degrees

EDIT: What if I put this in the graphing calculator and get the Peak value? y= (20sin(3.14y)) + (20sin(3.14y-1.5))
which I got the answer of 29.26754852234942V

would the phase shift be converting z (which is in radians) into degrees? 1.5*57.3 = 85.95

Last edited: Mar 9, 2010
4. MilK Member

Mar 1, 2008
25
0
peak value of sum = x + x

-z is the phase shift for waveform 2. phase shift of their sum = 0 + z