Fundamental electrokinetics problem calculation using Ohm's Law

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In summary, the fundamental electrokinetics problem involves analyzing the movement of charged particles in a fluid under the influence of an electric field. By applying Ohm's Law, which relates current density to electric field strength, one can derive the governing equations that describe the behavior of these particles. This approach enables the calculation of various parameters, such as current flow, charge distribution, and the effects of fluid properties on electrokinetic phenomena, ultimately aiding in the understanding of processes like electrophoresis and electroosmosis.
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annin
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New poster has been reminded to show their work when posting schoolwork type questions
Homework Statement
Please help me to find the voltage drop of the wire, and the terminal voltage.
Relevant Equations
R=V/I (Ohm's law)
For a consumer with a resistance of 2 ohms, it has an internal resistance of 0.3 ohms and a voltage of 130 Vwe switch on the power source. The resistance of each connecting thread is 0.15 ohms. What is the voltage drop on the line and what is the terminal voltage?
 
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Welcome to PF!
Please show your work and tell us where you're stuck.
 
  • #3
I can find the current flow with the equation I=V/Rtotal,
where Rtotal=R1+R2 and R1=2 ohm
R2=0,3 ohm

but after this I do not know how to continue. Hence I thought to use the electrical resistence of the wire for solving the problem, but I can't figure out how to use it correctly.
I would appreciate some guidance.
 
  • #4
annin said:
Homework Statement: Please help me to find the voltage drop of the wire, and the terminal voltage.
Relevant Equations: R=V/I (Ohm's law)

For a consumer with a resistance of 2 ohms, it has an internal resistance of 0.3 ohms and a voltage of 130 Vwe switch on the power source. The resistance of each connecting thread is 0.15 ohms. What is the voltage drop on the line and what is the terminal voltage?
annin said:
I can find the current flow with the equation I=V/Rtotal,
where Rtotal=R1+R2 and R1=2 ohm
R2=0,3 ohm

but after this I do not know how to continue. Hence I thought to use the electrical resistence of the wire for solving the problem, but I can't figure out how to use it correctly.
I would appreciate some guidance.
Is there a diagram that goes with this problem? I'm not understanding what is being asked. (Use the "Attach files" link below the Edit window to upload a diagram of the problem.)
 
  • #5
annin said:
it has an internal resistance
"It" being a battery?
annin said:
I can find the current flow with the equation I=V/Rtotal,
where Rtotal=R1+R2 and R1=2 ohm
R2=0,3 ohm
What about these "connecting threads"? What are they and where are they in the circuit?
annin said:
What is the voltage drop on the line
What line? No line was mentioned before. Is it the "threads"?
annin said:
what is the terminal voltage?
Think of the battery with internal resistance as two parts, an ideal battery (no internal resistance) with a resistor in series. The voltage across the ideal battery is 130V. Given the current in the circuit, what is the voltage drop across the internal resistance?
 

FAQ: Fundamental electrokinetics problem calculation using Ohm's Law

What is Ohm's Law and how is it applied in electrokinetics?

Ohm's Law states that the current (I) passing through a conductor between two points is directly proportional to the voltage (V) across the two points and inversely proportional to the resistance (R) of the conductor. It is mathematically expressed as V = IR. In electrokinetics, Ohm's Law is used to calculate the movement of charged particles through a medium by relating the electric field, current density, and electrical conductivity.

How do you calculate the electric field in an electrokinetic system using Ohm's Law?

The electric field (E) in an electrokinetic system can be calculated using a form of Ohm's Law adapted for continuous media. It is given by E = J/σ, where J is the current density and σ is the electrical conductivity of the medium. This relationship helps in determining how the electric field drives the movement of ions or charged particles in the system.

What are the common boundary conditions used in electrokinetic calculations?

Common boundary conditions in electrokinetic calculations include specified electric potentials (Dirichlet boundary conditions), specified electric fields or current densities (Neumann boundary conditions), and mixed boundary conditions that combine aspects of both. These conditions are essential for solving the governing equations and obtaining meaningful solutions for the electrokinetic behavior of the system.

How does the electrical conductivity of a medium affect electrokinetic calculations?

The electrical conductivity (σ) of a medium significantly affects electrokinetic calculations as it determines how easily current can flow through the medium. Higher conductivity implies lower resistance and thus higher current for a given electric field. This parameter is crucial for accurately predicting the movement of charged particles and the resulting electric fields in the system.

What role does the geometry of the system play in electrokinetic calculations using Ohm's Law?

The geometry of the system plays a critical role in electrokinetic calculations because it influences the distribution of the electric field and current density. For example, in a channel with varying cross-sectional area, the electric field and current density will vary along the length of the channel. Properly accounting for the geometry is essential for precise modeling and understanding of electrokinetic phenomena.

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