A Long Wire Is Known to Have a Radius Greater

question 31

Multiple Choice

A long wire is known to have a radius greater than 4.0 mm and to carry a current uniformly distributed over its cross section. If the magnitude of the magnetic field is 0.285 mT at a point 4.0 mm from the axis of the wire and 0.200 mT at a point 10 mm from the axis, what is the radius of the wire?

• A) 4.6 mm
• B) 7.1 mm
• C) 5.3 mm
• D) 12 mm
• E) 10 mm

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Definitions:

Variable Cost

Expenses that vary in proportion to the volume of goods or services produced in a business.

Opportunity Cost

The forfeiture of potential benefits from other options by selecting a specific one.

Fixed Costs

Business expenses that remain constant regardless of the level of production or sales activities, such as rent, salaries, and insurance.

Variable Costs

Costs that change in proportion to the level of goods or services a company produces.