Magnitude of Electric Field in Cell Membrane?

AI Thread Summary
The discussion focuses on calculating the magnitude of the electric field across a cell membrane, which has a potential difference of 0.060 V and a thickness of 9.00 x 10^-9 m. The formula used is E = V/r, where V is the voltage and r is the thickness. A participant initially calculated the electric field as 6.7E-6 V/m, but this was deemed incorrect due to the expectation of a larger value given the small thickness. The correct calculation should yield a much higher electric field strength, indicating a potential error in the exponent or arithmetic. The conversation emphasizes the importance of careful mathematical evaluation in physics problems.
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[SOLVED] magnitude of electric field.

Homework Statement



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 0.060 V exists across the membrane.

The thickness of the membrane is 9.00 x 10^-9 m. What is the magnitude of the electric field in the membrane?
in V/m


i believe the equation to be: E = V/r

not sure why .060 / 9.00 x 10^-9 would not work?

Homework Equations





The Attempt at a Solution





it says my answer of: 6.7E-6 is incorrect??
 
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You are dividing a number by a VERY small number. This means that your answer should be a very big number. 6.7E-6 is not very big. Check your math. I think you may have made an sign error with your exponent.
 
Okay thanks, 6.7E6
 
Anytime.:smile:
 

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