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Electric Current Physics Current Electricity Physics Class 12th

Two resistors R₁ = $(4 \pm 0.8) Ω a n d R_{2} = (4 \pm 0.4) Ω$ are connected in parallel. The equivalent resistance of their parallel combination will be:

Option 1 -

$(4 \pm 0.4) Ω$

Option 2 -

$(2 \pm 0.3) Ω$

Option 3 -

$(4 \pm 0.3) Ω$

Option 4 -

$(2 \pm 0.4) Ω$

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1 Answer

Answered by

alok kumar singh | Contributor-Level 10

2 months ago

Correct Option - 2

Detailed Solution:

$\frac{1}{R_{e q}} = \frac{1}{R_{1}} + \frac{1}{R_{2}} = \frac{1}{4} + \frac{1}{4}$

R_eq = 2

$\frac{Δ R_{e q}}{R_{e q}^{2}} = \frac{Δ R_{1}}{R_{1}^{2}} + \frac{Δ R_{2}}{R_{2}^{2}}$

$\begin{array}{l} \frac{Δ R_{e q}}{4} = \frac{0.8}{16} + \frac{0.4}{16} + \frac{1.2}{16} \\ R_{e q} = 0.3 \end{array}$

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Two resistors R₁ = $(4 \pm 0.8) Ω a n d R_{2} = (4 \pm 0.4) Ω$ are connected in parallel. The equivalent resistance of their parallel combination will be:

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Two resistors R1 = ( 4 ± 0 . 8 ) Ω a n d R 2 = ( 4 ± 0 . 4 ) Ω are connected in parallel. The equivalent resistance of their parallel combination will be:

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Two resistors R₁ = $(4 \pm 0.8) Ω a n d R_{2} = (4 \pm 0.4) Ω$ are connected in parallel. The equivalent resistance of their parallel combination will be: