Question

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

Answer 1

The above circuit shows resistances R₁ and R₂ connected in series with a battery of V volts.

Let the potential difference across R₁ be V₁ and the potential difference across R₂ be V₂.

V = V₁ + V₂    ...(i)

By Ohm’s law:

R = `V/I`

V = IR    ...(ii)

Applying Ohm’s law:

V₁ = IR₁    ...(iii)

V₂ = IR₂    ...(iv)

From the equations (i), (ii), (iii), and (iv), we get,

R = R₁ + R₂