Question

derive an expression for series connection and parallel connection

Answer 1

conider two resistors in series of 3 resistors with resistance R1,R2...R3 respectively. three connected to a battery of voltage V then find current i.

now as current is same in series total potential= sum of potentials of individual resistors... V= IR = IR1+IR2+IR3

                   V= I(R1+R2+R3)=IR

R=R1+R2+R3

similarly when they are in parallel as volatge is same and current varies

I= v/R = V/R1 +V/R2 +V/R3

1/R= 1/R1 +1/R2+1/R3 APPLY SAME FOR N RESISTORS

Answer 2

Answer:

The total resistance of a series circuit is equal to the sum of individual resistances." In a series circuit you will need to calculate the total resistance of the circuit in order to figure out the amperage. ... To calculate the total resistance we use the formula: RT = R1 + R2 + R3.