Electric Field and Force in a Cell Membrane

AI Thread Summary
The discussion centers on calculating the electric field and force within a cell membrane modeled as a parallel plate capacitor with a charge density of 7.31 x 10^-6 C/m². To find the electric field, the equation E = charge density/ε₀ is used, where ε₀ is the permittivity of free space. Participants express uncertainty about the value of ε₀, which is necessary for completing the calculations. Once the electric field is determined, the electric force on a potassium ion (K+) can be calculated using F = (electric field)(charge). Understanding these concepts is crucial for solving the problem effectively.
nic4birds
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Homework Statement


The membrane surrounding a living cell consists of an inner and an outer wall that are separated by a small space. Assume that the membrane acts like a parallel plate capacitor in which the effective charge density on the inner and outer walls has a magnitude of 7.31 x 10-6 C/m2. (a) What is the magnitude of the electric field within the cell membrane? (b) Find the magnitude of the electric force that would be exerted on a potassium ion (K+; charge = +e) placed inside the membrane.


Homework Equations


E=charge density/Eo
F=(electric field)(Charge)
E=q/(Eo)A
 
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nic4birds said:

Homework Statement


The membrane surrounding a living cell consists of an inner and an outer wall that are separated by a small space. Assume that the membrane acts like a parallel plate capacitor in which the effective charge density on the inner and outer walls has a magnitude of 7.31 x 10-6 C/m2. (a) What is the magnitude of the electric field within the cell membrane? (b) Find the magnitude of the electric force that would be exerted on a potassium ion (K+; charge = +e) placed inside the membrane.


Homework Equations


E=charge density/Eo
F=(electric field)(Charge)
E=q/(Eo)A
You seem to have missed out section three of the template: Attempted Solution...
 
for this problem i do not know how to start it, i believe that the 7.31 value is the charge density but i do not know what the other value Eo would be. once i can solve for the first part i will be able to calculate for the magnitude of the electric force
 
nic4birds said:
for this problem i do not know how to start it, i believe that the 7.31 value is the charge density but i do not know what the other value Eo would be. once i can solve for the first part i will be able to calculate for the magnitude of the electric force
Eo or ε0 is the permitivity of free space, which is a constant one has to look up.
 

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