Question

Derive an expression for resistors connected in series

Answer 1

Answer:

I will suppose that the 3 resistances are r1 r2 r3

simple : equivalent resistance r = r1+r2+r3

full complex:

in a series connection the potential difference across each resistor is same therefore we consider the pd to be v.

i=v/r

i1=v/r1

i2=v/r2

i3=v/r3

i1+i2+r3=r

v/r1+v/r2+v/r3=v/r

v(1/r1 + 1/r2 +1/r3)=v/r

1/r1 + 1/r2 +1/r3 = v/r*r

/r1 + 1/r2 +1/r3 = 1/r

therefore r1+r2+r3=r

Krishna