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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Definitions:

Rotator Cuff

A group of muscles and tendons that surround the shoulder joint, maintaining stability and allowing rotational movement.

Lateral Border

The outermost edge or boundary of an anatomical structure, situated farthest from the midline of the body.

Subscapularis

A muscle located beneath the scapula that helps rotate the arm and holds the humerus in place within the shoulder joint.

Extensor Carpi Radialis Brevis

A muscle in the forearm that assists in extending and abducting the wrist.