Circuit analysis current source problem

In summary, the problem involves finding the voltage V1 in a circuit shown by using the superposition theorem. The first attempt at a solution was incorrect, but after considering the 6A source and the 1A source separately, a correct solution was found. The 40Ω and 8Ω resistors are in series and the 80Ω and 120Ω resistors are in parallel.
  • #1
Jamessamuel
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0

Homework Statement


given the circuit shown, find V1.
12231610_1652042151703604_2077339994_n.jpg

Homework Equations

The Attempt at a Solution


see image:
am i right? Video says otherwise... I chose to use the superposition theorem here.
12200761_1652042148370271_1013343203_n.jpg


help appreciated,

regards,

james.
 
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  • #2
Jamessamuel said:

Homework Statement


given the circuit shown, find V1.
[ ATTACH=full]91899[/ATTACH]

Homework Equations

The Attempt at a Solution


see image:
am i right? Video says otherwise... I chose to use the superposition theorem here.
[ ATTACH=full]91898[/ATTACH]

help appreciated,

regards,

james.
That second image is very difficult to read.

It appears that you took the 80Ω and 120Ω to be a parallel combination, which is correct. However, that combination is NOT in series with the 8Ω resistor.
 
  • #3
SammyS said:
However, that combination is NOT in series with the 8Ω resistor.
I think they're considered in series for getting the current through them when the 1A supply is ignored, but must be separated to get individual resistor voltage drops. Once all individual voltage drops are gotten they are then combined (superpositioned?) for the answer.
 
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Likes SammyS
  • #4
surely this is correct?
12242271_1652116441696175_986558241_n.jpg
 
  • #5
Jamessamuel said:
surely this is correct?
[ ATTACH=full]91916[/ATTACH]
That's fine for the 6A source.

There is a different parallel/series combination you need to use for the 1A source. For this, there is no 56Ω combination.

(Thanks, insightful.)

Added in Edit:
The above refers to the following:
upload_2015-11-16_7-56-6.png


The 40Ω and 8Ω are in series.
That combination and the other two resistors, 80Ω and 120Ω, are all in parallel with the other.
 
Last edited:

1. What is a current source in circuit analysis?

A current source is an idealized component in a circuit that provides a constant flow of electrical current, regardless of the voltage or load connected to it. It is usually represented by a circle with an arrow pointing inward or outward to indicate the direction of current flow.

2. How do you solve a circuit analysis problem involving a current source?

To solve a circuit analysis problem with a current source, you need to use Kirchhoff's Current Law (KCL) and Ohm's Law. KCL states that the sum of all currents entering and exiting a node in a circuit is equal to zero, while Ohm's Law states that the current flowing through a component is equal to the voltage across it divided by its resistance. By applying these principles, you can determine the currents at different points in the circuit and analyze the behavior of the current source.

3. What is the difference between an ideal and non-ideal current source?

An ideal current source is an idealized component that provides a constant current regardless of the voltage or load connected to it. It has an infinite internal resistance and can maintain a constant current flow even when the load resistance changes. On the other hand, a non-ideal current source has a finite internal resistance, and the current it provides may vary depending on the load connected to it.

4. How do you calculate the voltage across a current source?

The voltage across a current source can be calculated using Ohm's Law. Since an ideal current source has an infinite internal resistance, the voltage across it is equal to the product of its current and the internal resistance. For a non-ideal current source, the voltage across it can be calculated by subtracting the voltage drop across its internal resistance from the voltage supplied by the source.

5. What are some common applications of current sources in circuits?

Current sources are commonly used in electronic circuits to provide a constant and stable current to components such as transistors, integrated circuits, and light-emitting diodes (LEDs). They are also used in battery charging circuits, where a constant current is needed to charge the battery efficiently. Current sources are also used in sensors and detectors, where a constant current is required to measure changes in resistance or capacitance.

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