Hi guys
I am struggling to find the power dissipated in the total circuit , my answer didn't match the solution in the book
the circuit is simple i used Kirchhoffs rules to find the following :
loop 1 :
$$10-10I_{1}-40I_{3} = 0$$
loop 2:
$$20-20I_{2}-40I_{3} = 0$$
and $$ I_{1}+I_{2}=I_{3}$$...
Hello all PF members!
I was wondering about the power dissipated by resistor at high frequency which is:
##P=Re\left \{ U\cdot I^{*} \right \}=Re\left \{ \frac{\left |V^{+} \right |^{^{2}}}{2\left |Z_{c} \right |}\cdot (1-\left |\Gamma \right |^{2} )\right \}##, (1)
where:
##Z_{c}## -...
I understand that when using the equation I^2 * R that current is meant to be constant in each component? I got the idea from this video
So how can we use this equation to find the relationship between varying current against power? As the current is at a constant?...
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Homework Statement
A wire shaped as a semi-circle of radius a rotates about the axis OO’ with a constant angular velocity ω in a uniform magnetic field with induction B (attached figure). The plane of the rectangular loop is perpendicular to the magnetic field direction. The total resistance of...
Here is an image with information: https://i.snag.gy/UMCRig.jpg
I have calculated the total power dissipation as 11W. What I don't see is why R1 has a higher dissipation rate than R2/R3, and my main question is how do I calculate the power dissipation of R1?
I get that R2/R3 are in series so...
1. The problem
Given a circuit with a 30V source and five resistors. The circuit can be drawn as two boxes. Resistor 1 (R1 = 300ohm) is in series with the source. R2 (300ohm) in the middle of the two boxes, and the remaining resistors (550 ohm) in series at the other side of the box.
The...
Homework Statement
Homework EquationsThe Attempt at a Solution
I am surprised that this question came up, I haven't learned ac circuits yet. I don't know how to solve this. I just added both values and current and divide it by two, which gives me 1.5A, since I thought it's the average but I'm...
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Homework Statement
NOTE: Image uploaded with thread shows problem in clearest possible form.
V = (45v)sin(80[pi] t)
Resistors 1 and 2 = 50 Ohms
Inductor 1 = 20 mH
Inductor 2 = 2.5 mH
Capacitor = 50 uF
a) Find the power dissipated by each resistor.
b) At what frequency will both resistors...
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Hello
Here is a problem of Pozar's Book(mircowave).
and here is solution:
my problem is I don't know how he obtain -40.6 because
|T|^2 (T is Reflection Coefficient ) is return power and 1-|T|^2 is transfer powe but 10log none of them return -40.6 , what does -40.6 and how can calculate it?
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Homework Statement
We have the circuit in the figure.I have to find the average power consumed by all the elements and the source.
Homework Equations
P=0.5*(I^2)*R
P=-VmImcosθ/2
The Attempt at a Solution
The inductor consumes zero inductive power.
I apply nodal analysis at node Vo
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Hello Forum,
It is well known that the electrical power dissipated (in the form of heat) by a resistor of resistance R connected to a battery of voltage V is:
P_diss = (V^2)/ R or equivalently P= (I^2)*(R)
Clearly the smaller the resistance R, the more the dissipated power because R is at...
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Homework Statement
Basically, I need to know the power dissipation (W) for three resistors using aw 12V battery: 120, 80, and 50 ohms.
https://webwork2.uncc.edu/webwork2_files/tmp/Fall2014-Engr1201-Common/img/2ff2f0ce-cb10-3786-8109-c42346130316___1a2e5eeb-8657-3983-941f-b7d8a9123afa.gif...
Hey Guys,
Can you see what is wrong with this circuit?
It looks fine to me but I am being told that it is incorrect and will not work. I am pretty sure I am wrong and am willing to ask for help in understanding why this wouldn't work.
Please see attached picture for further info and any...
Hello,
This is my first post on this forum and I better warn you that there maybe some poor grammer and spelling mistakes. Given what I had to aggree to in order to register I'd like appologies in advance to all those people who are offended by such things.
I'm looking at a problem with...
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Homework Statement
i let r = 1 ohm, so i get effective r = 1.5 ohm, , since P=VI, i get my I = 8A, so i get the power dissipation of RESISTOR P = 8W , so the 4W remaining for both Q AND R , why power of R is 2W? i hope someone can explain this.
Homework Equations
The Attempt at a...
Homework Statement
A z-polarized incident EM waves hits a small charge (-q) bounded to a massive charge (+q) with spring constant k0 and frequency ω.
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Homework Statement
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difference "power dissipation" and "actual power dissipation"
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Homework Equations
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Homework Statement
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I...
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An extension cord made of two wires of diameter 0.129 cm (no. 16 copper wire) and of length 1.2m (4ft ) is connected to an electric heater which draws 15.0A on a 120 V line. How much power is dissipated in the cord?
Homework Equations
P = IV
R = ρL / A
P = V^2/R...
Right, so I was going over some old (basic) electromagnetism principles (to make sure it doesn't all fall out of my head). And I was thinking about two resistors in parallel, assuming some constant dc voltage across them. And I was thinking about the power dissipated by this simple circuit. And...
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Calculate the power dissipated in R1, R2 and R
[/b]
Previously i worked out the Current I1, I2 and I3 so i planned to use this to calculate the power dissipated;
For current i got;
I1= 0.8409 A
I2= -0.4545 A
I3= 0.39 A
I used I^2/R to get the following answers
R1 =...
This question is in reference to the diagram here:
http://imageshack.us/f/17/ecediagram.jpg/
Find the average power dissipated on the resistor.
Assume Vth for the diodes is 1V, N1 = 1000, N2 = 100, the transformer is ideal (non-lossy), and V(t) is a purely sinusoidal voltage with frequency...
the equation P = (E2R) / [(R-r)2 + 4Rr]
We say that when R=r , P = E2/4R which is said to be maximum..
But if I say R→∞ , then r→0 and then P = E2/R which is greater..
So, shouldn't power be maximum for max R ?
During a Lab we had a simple purely resistive circuit hooked up to a 10 VDC power supply with an adjustable voltage output. In order to determine the power dissipated by the circuit we were asked to determine the source voltage while the circuit was DISCONNECTED... we were not told why... In the...
I've been looking over how to find power dissipation for voltage regulators, op-amps, comparators, logic gates, and amongst other things.
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From what I understood so far I've seen
PDstatic = Vcc*Icc where Vcc and Icc...
i got part (a) by using the equation Vab + E - Ir
Which gives 26.57V (also the current = 1.171A)
Having trouble getting the power dissipated, any ideas?
Homework Statement
Heater dissipates 500W when applied potential diference is 110V and wire is 800C. How much power would it dissipate if the wire temperature were held at 200C?
Homework Equations
a=4.0e-4
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there are 3 resistors of, different values. 470o,22o and 100o. but each one is 500W
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the...
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The current through a resistor is i(t) = 2sin(30t + 169°), and R = 50Ω
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The Attempt at a Solution
I feel stupid...
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For the circuit shown, find the power dissipated by the 10.0 ohm resistor.
(as attached)
Homework Equations
P=IV=I2R=V2R
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The Attempt at a Solution
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