Fundamentals of Electrical Engineering Circuit Basics Question

In summary, the conversation discusses the fundamentals of electrical engineering and specifically the concept of circuit basics. The question at hand is to find the values of p1, p2, p3, and p4. The solution involves using the equation p=vi and the concept of power conservation (ƩP=0). The summary also includes a clarification on how to find the voltage for p3, which is a dependent voltage source with a current of 4A. It is explained that the voltage can be calculated by multiplying the current by 0.6.
  • #1
Varro
2
0
"Fundamentals of Electrical Engineering" Circuit Basics Question

Homework Statement


07ELr.jpg

I am asked to find p1, p2, p3, p4.

Homework Equations


p=vi
ƩP=0

The Attempt at a Solution


p1=(5)(-9)
=-45
p2=(2)(9)
=18
p4=(3)(5)
=15

p3=v(.6i)
=v(.6(4))
=v(2.4)
I know that v=5 and p3=12, but I don't know why v=5.

I do perfectly fine finding p1, p2, and p4, but I am having difficulty figuring out how to find the voltage on p3 to get the power. I am trying to refrain from using the law of the conservation of energy (ƩP=0), since a previous example I tried to figure out before gave me the same problem.
 
Physics news on Phys.org
  • #2


The diagram shows I = 5A. So the voltage on the controlled source should be 5*0.6 = 3V.
 
  • #3


gneill said:
The diagram shows I = 5A. So the voltage on the controlled source should be 5*0.6 = 3V.

I am talking about the dependent voltage source, p3. The current is labeled as 4A.
 
  • #4


Varro said:
I am talking about the dependent voltage source, p3. The current is labeled as 4A.

Yes, the current through the controlled source is labelled as 4A. But the controlled source voltage is stated to be 0.6I, and I = 5A.
 
  • #5


To find the voltage on p3, you can use Ohm's Law, which states that voltage (V) is equal to current (I) multiplied by resistance (R). In this circuit, p3 has a resistance of 0.6 ohms, so you can use the equation V=IR to find the voltage. Plugging in the values, you get V=(0.6)(4)=2.4 volts. This is why v=5, because the voltage across the entire circuit is 5 volts. Additionally, the power in p3 is found by using the equation P=VI, where V is the voltage you just calculated and I is the current, which is given as 4 amps. Therefore, P=(2.4)(4)=9.6 watts. Remember to always check the units and make sure they are consistent (i.e. volts x amps = watts).
 

1. What is the difference between AC and DC circuits?

AC (alternating current) circuits have a constantly changing direction of current flow, while DC (direct current) circuits have a constant direction of current flow. AC circuits are typically used for long-distance power transmission, while DC circuits are used for electronic devices.

2. What is the purpose of a resistor in an electrical circuit?

A resistor is used to limit the flow of current in a circuit. It is often used to control the amount of voltage and current in a circuit, and can also be used to reduce heat and protect other components from damage.

3. How do capacitors and inductors work in a circuit?

Capacitors store electrical energy in an electric field, while inductors store energy in a magnetic field. They can both be used to control the flow and timing of current in a circuit, and are often used in filters, oscillators, and other electronic components.

4. What is the difference between series and parallel circuits?

In a series circuit, the components are connected in a single loop, so the current flows through each component in order. In a parallel circuit, the components are connected in multiple branches, so the current can flow through each component independently. Series circuits have a single path for current flow, while parallel circuits have multiple paths.

5. What is the purpose of a fuse or circuit breaker?

Fuses and circuit breakers are safety devices that protect electrical circuits from overloading and short circuits. They work by interrupting the flow of current when it exceeds a certain level, preventing damage to the circuit and potential fires.

Similar threads

  • Engineering and Comp Sci Homework Help
Replies
1
Views
708
  • Engineering and Comp Sci Homework Help
Replies
32
Views
3K
  • Engineering and Comp Sci Homework Help
Replies
0
Views
415
  • Engineering and Comp Sci Homework Help
Replies
1
Views
1K
  • Engineering and Comp Sci Homework Help
Replies
1
Views
1K
  • Engineering and Comp Sci Homework Help
Replies
14
Views
1K
  • Engineering and Comp Sci Homework Help
Replies
26
Views
2K
  • Mechanical Engineering
Replies
2
Views
682
  • Engineering and Comp Sci Homework Help
Replies
6
Views
7K
  • Precalculus Mathematics Homework Help
Replies
5
Views
2K
Back
Top