Could Somebody help me please? EMF in parallel

In summary, the problem involves finding the magnitudes and directions of current through two resistors in a parallel circuit with two batteries. The first equation for current flow has a mistake in the sign and can be corrected. Another equation can be written to solve for one of the currents, which can then be used to solve for the other current. The final current can be found by adding the two solved currents.
  • #1
Drakon25th
Ok, the question says: "Find the magnitudes and directions of the current through the 22 ohm and 15 ohm resistors (the internal resistance of the batteries is negligible)"

My question is how do i determine this if there's a second emf in the problem?

here's a picture of the problem:
picture

i tried using Kirchoff's loop law at first, first determining these two formulas:
0=E1-I1R1-I2R2
=9.0 - 22I1 - 15I2
I1 = .41 - .68I2

and

0=E2 - I2R2
= 6-15I2
I2 =.40

The problem is the second equation doesn't incorporate I3, so i can't use I3 = I2 + I1, so I'm stuck here.
Then I thought about using Ohm's law, but I am not sure how do i use E1 in terms of the parallel circuit to determine the total current going through the whole circuit. Please help me someone :smile:
 
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  • #2
by the way, the directions for I1, I2, and I3 in the picture are my predictions on the current flow throughout the circuit
 
  • #3
bump, please help me =(
 
  • #4
I'm no electrical engineer, but...

It seems to me that given your choices for current flow (and I am presuming you are using conventional current, which imagines that a positive charge is what is flowing), your first equation has a bogus sign and should be:

0=E1-I1R1+I2R2.

Does it help to write another equation based on the third path of flow? That is the one with the two batteries and R1 in it:

E1+E2=I1R1.

That would allow you to immediately solve for I1. Then You could put that value in my corrected version of your first equation and solve for I2.
 
Last edited:
  • #5
so there would be no I3?
 
  • #6
If my analysis is correct, then it gives you I1 and I2, and as you said, you can then get I3 by adding those two: I3 = I2 + I1.
 
  • #7
alright, thank you so much for the help :)
 

1. What is EMF?

EMF stands for electromagnetic force, which refers to the force created by the presence of electrically charged particles. It is a fundamental force of nature and is responsible for many phenomena, including electricity and magnetism.

2. How does EMF work in parallel circuits?

In a parallel circuit, EMF refers to the voltage difference between two points in the circuit. This voltage difference creates an electric field that allows charges to flow through the circuit. The total EMF in a parallel circuit is equal to the sum of individual EMF values in each branch of the circuit.

3. Can EMF in parallel circuits be harmful?

EMF in parallel circuits is typically not harmful to humans. However, high levels of EMF exposure can potentially cause health issues, such as headaches and fatigue. It is important to follow safety regulations and guidelines when working with EMF.

4. How can I measure EMF in parallel circuits?

EMF can be measured using a device called an EMF meter. This device measures the strength of the electric field and can provide readings in units such as volts per meter or milligauss. It is important to use a calibrated meter and follow proper measurement procedures.

5. What are some common applications of EMF in parallel circuits?

EMF in parallel circuits has many practical applications, such as in household wiring, electronic devices, and power distribution systems. It is also used in medical imaging technologies, such as MRI machines, to create detailed images of the body.

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