A Long Hollow Cylindrical Conductor (Inner Radius = 2

question 4

Multiple Choice

A long hollow cylindrical conductor (inner radius = 2.0 mm, outer radius = 4.0 mm) carries a current of 12 A distributed uniformly across its cross section. A long wire which is coaxial with the cylinder carries an equal current in the same direction. What is the magnitude of the magnetic field 3.0 mm from the axis?

• A) 1.1 mT
• B) 1.4 mT
• C) 1.7 mT
• D) 2.0 mT
• E) 0.2 mT

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Definitions:

Dimensional-analysis

A method in physics and engineering to check the consistency of equations involving physical quantities by tracking units and dimensions.

Seconds

The basic unit of time in the International System of Units (SI), equal to one sixtieth of a minute.

Hours

A period of time equal to a twenty-fourth part of a day and night and universally understood to be 60 minutes.

Dimensional-analysis

A mathematical technique used to convert units of measurement without changing the dimensional or physical value.