Field of a Long Wire: the Figure Shows Two Long

question 12

Multiple Choice

Field of a long wire: The figure shows two long, parallel current-carrying wires. The wires carry equal currents I₁ = I₂ = 20 A in the directions indicated and are located a distance d = 0.5 m apart. Calculate the magnitude and direction of the magnetic field at the point P that is located an equal distance d from each wire. (μ₀ = 4π × 10^-7 T ∙ m/A)

• A) 8 µT downward
• B) 8 µT upward
• C) 4 µT downward
• D) 4 µT upward
• E) 4 µT to the right

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Definitions:

Oligopoly

A market structure characterized by a small number of large firms dominating the market, which have significant control over price and high barriers to entry.

Nineteenth Century

The period from 1801 to 1900, characterized by industrialization, colonial expansion, and significant social, economic, and political changes.

Railroads

Transportation systems using trains to move goods and passengers along tracks, playing a key role in economic development by facilitating trade and movement.

Price War

A collapse of prices when tacit collusion breaks down.