Question

Show how you would connect two 4 ohm resistors to produce a combined resistance of (a) 2 ohm (b) 8 ohm

Answer 1

$\huge{\underline{\bf{\green{Solution:-}}}}$

$\rm\:for \: 2\Omega \: resistance \: \:$

Connecting $4\Omega$ resistors in parallel combination.

$\mapsto \rm\:\frac{1}{R_P}=\frac{1}{R_1}+\frac{1}{R_2}\\\\\:$

$\mapsto \rm\:\frac{1}{R_P}=\frac{1}{4}+\frac{1}{4}\\ \\\mapsto \rm\: \frac{1}{R_P} = \frac{2}{4} \\ \\ \mapsto \rm \: \frac{1}{R_P} = \frac{1}{2} \\ \\ \mapsto \bf\blue{ \: R_P = 2 \Omega}$

Thus, we get $2\Omega$ resistance.

Connecting 2 resistors of $4\Omega$ in series.

$\mapsto \rm\:R=R_1+R_2\:\\\\\mapsto\rm\:R= 4\Omega+4\Omega\\\\\mapsto\bf\blue{R=8 \Omega}$

If we connect 2 resistors of 4 ohm in series we get 8 ohm resistance.

and if we connect 2 resistors of 4 ohm in parallel combination then we get 2ohm resistance.

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Answer 2

$\huge \red{answer}$

If we connect 2 resistors of 4 ohm in series we get 8 ohm resistance.

and if we connect 2 resistors of 4 ohm in parallel combination then we get 2ohm resistance.