How Strong is the Electric Field Across a Cell Membrane?

AI Thread Summary
The electric field across a cell membrane is influenced by the potential difference of approximately 0.0730 V and the membrane's thickness of 8.22E-9 m. A user attempted to calculate the electric field using various formulas but encountered errors, indicating potential confusion with the application of the equations. It was suggested that the problem could be approached by treating the membrane as a capacitor, which relates electric field (E), voltage (V), and thickness. Clarification on the correct formulas and methods for calculating the electric field is needed. Understanding the relationship between these variables is crucial for accurate calculations.
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The inner and outer surfaces of a cell membrane carry a negative and positive charge, respectively. Because of these charges, a potential difference of about 0.0730 V exists across the membrane. The thickness of the membrane is 8.22E-9 m. What is the magnitude of the electric field in the membrane?

so i took .0730V and multiplied it by 1.60E-19C to get an answer in joules. i ended up getting 1.168E-20J. i then took that and divided it by .0730V to get an answer in coulombs. and i got 1.6E-19C for that. then i took my answers and plugged them into the equation. E=8.99E9(1.6E-19)/(8.22E-9)^2. then the final answer i got was . and i punched it in and it was wrong. i don't know if i am using the wrong formulas. most likely that's the case. so if you see something I am doing wrong and can point me in the right direction that would be a great help. thanks.
 
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wait, too hard, and I'm thinking youre confused re maybe the notion of a test charge. I think, iirc, you just need to treat this as a ccapacitor which relates E,V, and thickness.
 

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