Problem Solving

Sodium ions () are flowing through a cylindrical ion channel which has a diameter of 0.85 m and is 5 m long. There is a potential difference of 225 mV between the ends of the channel. The sodium ions have a drift velocity through the channel of 0.015 and in a period of 1 ms a total of 15 x ions exit the channel.

For Group 1, (a) What total charge exits the channel in a time period of 1 ms?

 

Please show all steps for further problem solving. thank you,

A calcium ion Ca^++ enters with a velocity of zero a region ofuniform electric field 200N/C pointing east. What is the speedafter 50ms?

Please go over concepts and intution for this problem.

Please show all steps for further problem solving. Thank you,

The Fermi energy for copper is 7.05 eV. copper has a density of8920 kg/m3 and an atomic mass of 63.5. On average, how manyelectrons does an atom contribute to the conduction band?

I'm a bit puzzled regarding scalar and vector potential functions. What problem-solving advantages do they offer compared to dealing directly with the electric and magnetic fields?