Question

With the help of a circuit diagram, deduce the equivalent resistance of two resistances connected in series​

Answer 1

Answer:

Fig. shows two resistances R1 and R2connected in series with a battery of V volts.

Let the p.d. across R1 is V1 and the p.d. across R2

is V2

s.t.V=V1 +V2 -----------------------(1)

Let the equivalent resistance be R and current flowing through the whole circuit is I.

By Ohm's law,

IV =R

V=I×R ---------------------------(2)

Applying ohm's law to both R1 and R2 ,

V1=I×R -----------------------(3)

V2 =I×R2 ----------------------(4)

From eqs. (1) , (2) , (3) and (4) , we get

I×R=I×R1 +I×R2

I×R=I×(R1 +R2 )

R=R1 +R2