14. Describe exactly how, in a cell composed of a tin and a silver plate with dilute sulphuric acid as electrolyte, the current inside and outside of the cell will flow.
15. Describe the phenomenon of polarization.
16. What is local action of a cell? How may it be prevented?
17. Into how many classes may cells be divided? Which class is most used in telephony?
18. Describe the LeClanché cell.
19. Sketch and describe an excellent form of dry cell.
20. Show the conventional symbols for batteries.
21. Sketch and describe the generator shunt switch and the generator cut-in switch.
22. How may a pulsating current be derived from a magneto generator?