A Long Vertical Wire Carries a Steady $70 \mathrm {~A}$ Current as Shown in the Figure, a Pair of Horizontal

question 64

Multiple Choice

A long vertical wire carries a steady $70 \mathrm {~A}$ current. As shown in the figure, a pair of horizontal rails are $0.20 \mathrm {~m}$ apart. $\mathbf { A } 20 - \Omega$ resistor connects points $a$ and $b$ , at the end of the rails. $\mathbf { A }$ bar is in contact with the rails, and is moved by an external force with a constant horizontal velocity of $0.90 \mathrm {~m} / \mathrm { s }$ to the right, as shown. The bar and the rails have negligible resistance. At the instant that the bar is $0.20 \mathrm {~m}$ from the wire, what are the induced current in the resistor and its direction through the resistor? $\left( \mu _ { 0 } = 4 \pi \times 10 ^ { - 7 } \mathrm {~T} \cdot \mathrm { m } / \mathrm { A } \right)$

• A) \(0.63 \mu \mathrm { A }\), from \(b\) to \(a\)
• B) \(0.32 \mu \mathrm { A }\), from \(b\) to \(a\)
• C) \(1.9 \mu \mathrm { A }\), from \(b\) to \(a\)
• D) \(0.32 \mu \mathrm { A }\), from \(a\) to \(b\)
• E) \(0.63 \mu \mathrm { A }\), from \(a\) to \(b\)

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Definitions:

Chromosomes

Structures found within cells that contain DNA and proteins, responsible for carrying genetic information.

X-linked Color-blindness

A genetic condition affecting the ability to see colors correctly, passed down through genes located on the X chromosome.

Colorblind

A condition where a person is unable to distinguish certain colors, typically due to the absence or malfunction of certain color-detecting cells in the eye.

Probability

A measure of the likelihood that an event will occur, often quantified as a number between 0 and 1.