Magnitude and direction of the current in conductor

In summary, the person has solved three circuit problems and is looking for confirmation on their answers. They have included diagrams and explanations of their thought process. The first problem asks about the magnitude and direction of current in conductor PQ, and the person chose choice #4 because it correctly shows 5 A toward Q. The second problem asks which diagram correctly shows currents near junction P, and the person chose choice #4 because it is the only one with arrows indicating current traveling near P. The last problem involves determining various values in a complex circuit using the V=IR formula, and the person has included their answers and detailed process of breaking down the circuit to arrive at those answers. They are seeking someone to confirm their answers.
  • #1
bap902
26
0
I have a few questions on three circuits problems that I have already solved. I explained how I arrived at my answers and included diagrams. I would appreciate any help in confirming that my answers are correct. Thank you!

1. The diagram below shows electric currents in conductors that meet at junction P.

http://www.stmary.ws/physics/home/marys_java/regents/Januar14.gif

What are the magnitude and direction of the current in conductor PQ? (1) 9 A toward P (2) 9 A toward Q (3) 5 A toward P (4) 5 A toward Q

I chose choice #4, 5 A toward Q because when 3 and 4 are added you get 7. But, because of the 2 moving in the opposite direction, it takes away from the overall total of 7 leaving you with 5.

2. Which diagram below correctly shows currents traveling near junction P in an electric circuit?

http://www.stmary.ws/physics/home/marys_java/regents/June0114.gif

(1) 1 (2) 2 (3) 3 (4) 4

I chose choice #4 because that is the only one where all the arrows correctly show that that the current is traveling near junction P. The arrows indicate the direction of the current toward the junction.

3. Determine the following using the figure below:
http://img509.imageshack.us/img509/8186/circuitoh0.png

R(total)= 25 ohms
I(total)= 4 amps
V(x-->y)= 20 volts
V(y-->z)= 20 volts
V(x-->z)= 40 volts
I(5 ohm resistor)= 1.3 amps
Power(10 ohm resistor - not the parallel ones)= 160 watts
Power (15 ohm parallel resistors)=26.7 watts

I included my answers as well as how I broke down the complex circuit into a simple circuit so I could arrive at those answers using the V=IR formula and working backwards.
 
Last edited by a moderator:
Physics news on Phys.org
  • #2
Anyone?
 
  • #3
Bump.
 
  • #4
The answers looks correct to me!
 

1. What is meant by the magnitude of current in a conductor?

The magnitude of current in a conductor refers to the strength or intensity of the flow of electric charge through the conductor. It is measured in amperes (A) and is directly proportional to the voltage and inversely proportional to the resistance in the circuit.

2. How is the direction of current flow determined in a conductor?

The direction of current flow in a conductor is determined by the direction of the flow of positive charges. Conventionally, current is said to flow from the positive terminal of a battery to the negative terminal, even though in reality, negatively charged electrons flow in the opposite direction.

3. What factors affect the magnitude of current in a conductor?

The magnitude of current in a conductor is affected by the voltage applied to the circuit, the resistance of the conductor, and the type of material the conductor is made of. Additionally, the temperature, length, and cross-sectional area of the conductor can also impact the magnitude of current flow.

4. How does the magnitude of current change in a series circuit?

In a series circuit, the magnitude of current remains the same at all points as there is only one path for the current to flow through. This means that the current is not divided but remains constant throughout the circuit. However, the voltage drop across each component may vary depending on their individual resistance.

5. How does the direction of current change in a parallel circuit?

In a parallel circuit, the current is divided into branches, and the direction of current flow can vary in each branch. However, the total current entering the circuit is equal to the sum of the currents in each branch. This means that the total current in a parallel circuit is greater than the current in any individual branch.

Similar threads

  • Introductory Physics Homework Help
Replies
6
Views
962
  • Introductory Physics Homework Help
Replies
18
Views
2K
  • Introductory Physics Homework Help
Replies
3
Views
552
  • Introductory Physics Homework Help
Replies
28
Views
1K
  • Introductory Physics Homework Help
Replies
9
Views
1K
  • Introductory Physics Homework Help
Replies
1
Views
178
  • Introductory Physics Homework Help
2
Replies
40
Views
876
  • Introductory Physics Homework Help
Replies
5
Views
456
  • Introductory Physics Homework Help
Replies
3
Views
1K
  • Introductory Physics Homework Help
Replies
7
Views
1K
Back
Top