Field of a Circular Loop: a Long Straight Very Thin

question 20

Multiple Choice

Field of a circular loop: A long straight very thin wire on the y-axis carries a 10-A current in the positive y-direction. A circular loop 0.50 m in radius, also of very thin wire and lying in the yz-plane, carries a 9.0-A current, as shown. Point P is on the positive x-axis, at a distance of 0.50 m from the center of the loop. What is the magnetic field vector at point P due to these two currents? (μ₀ = 4π × 10^-7 T ∙ m/A)

• A) zero
• B) -8.0 × 10^-6 T
• C) (+4.0 × 10^-6
• T) - (4.0 × 10^-6
• D) (-4.0 × 10^-6
• T) - (4.0 × 10^-6
• E) (-4.0 × 10^-6
• T) - (80 × 10^-6

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Definitions:

Investment in Equipment

Capital expenditure on physical assets like machinery and equipment intended to be used in the production of goods or services.

Straight-Line Depreciation

A method of allocating the cost of a tangible asset over its useful life in consistent annual amounts.

Remodelling

The process of updating or altering the structure, layout, or appearance of an existing building or space.

Discount Rate

The interest rate used to discount future cash flows to their present value, often used in the context of evaluating investments or projects.