The blacked-out part are the questions I already have answers to. Please answer

Question

The blacked-out part are the questions I already have answers to. Please answer the un-blacked out questions.

Distributions of electric charges in a cell play a role in moving ions into and out of a cell. In this situation, the motion of the ion is affected by two forces: the electric force due to the non-uniform charge distribution in the cell membrane, and the resistive force (viscosity) due to colliding with the fluid molecules. In order to begin our analysis of this, let's consider a toy model in which the ion is moving in response to electric forces alone. Charge in a cell membrane are distributed along the opposite sides of the membrane uniformly. This leads to an (on the average) constant electric field the membrane. A simple model that gives this kind of field is two large parallel plates close together. The field between the plates is approximately constant pointing from the negative to the parallel plate. This results in a charge feeling a constant force anywhere between the plate (sort of like flat-gravity turned sideways). Outside of the plates the electric fields from the two plates cancel and there is not force. A sodium ion enters the channel. As it is accelerated, it will pass through the points marked a and b. What will be the ranking of the magnitudes of the electric force felt by the ion at points a and b? What will be the ranking of the magnitudes of the acceleration of the ion at points a and b? The electric field between the plates (inside the membrane) is about 10^7 N/C. Estimate: The electric force on the ion when it is in the center of the channel. The acceleration of the ion when it is in the center of the channel. a = nm/s^2 The potential energy difference of the ion as it crosses from one side of the plates to the other. U = J Explain your reasoning. The kinetic energy the ion would gain as it crosses from one side of the plates to the other. kE = J Explain your reasoning.

Explanation / Answer

2.2

m=22 amu=22*1.6*10^(-27) kg

Since E is constant ,a is also consant given by

a=qE/m=4.55*10^(13) m/s^2

2.3

voltage=E*d

where d is distance between two plates

potential energy difference=e*change in voltage=1.6*10^(-12)*d

2.4

kinetic energy gain=change in potential energy=1.6*10^(-12)*d

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