A Long Straight Wire of Radius R Carries a Current $\mu$

question 55

Multiple Choice

A long straight wire of radius R carries a current density J = kr A/m² where k is a constant.The magnetic field for r < R is (Hint: Current enclosed .)

• A)\(\mu\)₀kr²/2
• B)\(\mu\)₀kr²/3
• C)2\(\pi\mu\)₀kr
• D)2\(\pi\mu\)₀kr/2
• E)none of the above

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Definitions:

Futures Positions

Futures positions are commitments to buy or sell a specified amount of a commodity, currency, or financial instrument at a specified price on a set future date.

Marking To Market

Marking to market is an accounting practice where assets and liabilities are adjusted to their current market values rather than their book values.

Margin Call

A demand by a broker that an investor deposit further cash or securities to cover possible losses.

Variation Margin Check

A financial safeguard measure in futures trading that involves calculating and settling the gains or losses on open contracts to ensure enough capital exists to cover potential losses.