Question

Question 4: What is the significance of those strange “36.79%” and “63.21%” numbers the procedure? That is, where do they come from? Hint: they’re not your professor’s favorite numbers.

Question 5: Why does shorting the resistor (placing a wire across contacts 3 and 4) help to speed up the discharging or charging processes?

Answer 1

4)T numbers depicts the time constants for the capacitor i.e. amount of charge i.e 1/e times the total value for charging and discharging process of capacitor.

so time constant is the time when the capacitor charge becomes (1/e) or 36.79% of total value or when it is discharged 63.21% of total value (1-1/e).

5) Although here circuit diagram for contact 3 and 4 is not given but I am answering it. so if the resistor is shorted so there will be bo voltage drop across it i.e. no resistance to current flow so the current can easily go into or out of capacitor and thus charge so the rate of charging and discharging will increase.