If Two Resistors with Resistances $R_{1}$ And $R_{2}$ Are Connected in Parallel, as in the Figure, Then the in Parallel

question 138

Multiple Choice

If two resistors with resistances $R_{1}$ and $R_{2}$ are connected in parallel, as in the figure, then the total resistance $R$ measured in ohms ( $\Omega$ ) , is given by $\frac{1}{R}=\frac{1}{R_{1}}+\frac{1}{R_{2}}$ . If $R_{1}$ and $R_{2}$ are increasing at rates of $0.1 \Omega / s$ and $0.2 \Omega / s$ respectively, how fast is $R$ changing when $R_{1}=75$ and $R_{2}=100$ ?
Round the result to the nearest thousandth.

• A) \(0.1596 ~\Omega / \mathrm{s}\)
• B) \(1.1974 ~\Omega / \mathrm{s}\)
• C) \(0.1454 ~\Omega / \mathrm{s}\)
• D) \(0.0694 ~\Omega / \mathrm{s}\)
• E) \(0.1688 ~\Omega / \mathrm{s}\)

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