Nerve cells transmit electric signals through their long tubular axons. These signals propagate due to a sudden rush of Na+ ions, each with charge +e, into the axon. Measurements have revealed that typically about 5.7×10^11 Na+ ions enter each meter of the axon during a time of 7.0 ms. What is the current during this inflow of charge in a meter of axon?

Explanation:

For this case we have the following info given:

Number of Na+ ions

Each ion have a charge of +e and the crage of the electron is

The time is given if we convert this into seconds we got:

Now we can use the following formula given from the current passing thourhg a meter of nerve axon given by:

Where N represent the number of ions, e the charge of the electron and Q the total charge

If we replace on this case we have this:

And from the general definition of current we know that:

And since we know the total charge Q and the time we can replace:

The current during the inflow charge in the meter axon for this case is

r=rho l/a where a is the area, l is the length and rho is resistivity so the greater the area the lesser the resistance thats why the earth pin is thicker bcos current follow the shortest path, so less resistive .

it is a negative acceleration