Question

A coil of 100 turns, carrying a current of 5A, is placed in a magnetic field of 2T. The area of each turn is 0.01 m\(^2\). What is the magnetic moment of the coil?

• A. 0.5 Am\(^2\)
• B. 5 Am\(^2\)
• C. 2 Am\(^2\)
• D. 1 Am\(^2\)

Hint:

Remember: The magnetic moment of a coil is directly proportional to the number of turns, the current, and the area of each turn.

Answer 1

The Correct Option is B

Magnetic Moment of a Coil 

We are given the following data:

• Number of turns, \( N = 100 \)
• Current, \( I = 5 \, \text{A} \)
• Magnetic field, \( B = 2 \, \text{T} \)
• Area of each turn, \( A = 0.01 \, \text{m}^2 \)

Step 1: Recall the formula for the magnetic moment of a coil:

The magnetic moment \( \mu \) of a coil is given by the formula:

\[ \mu = N \cdot I \cdot A \]

Where:

• \( \mu \) is the magnetic moment,
• \( N \) is the number of turns,
• \( I \) is the current,
• \( A \) is the area of each turn of the coil.

Step 2: Substitute the known values into the formula:

\[ \mu = 100 \cdot 5 \cdot 0.01 = 5 \, \text{A} \cdot \text{m}^2 \]

Conclusion:

The magnetic moment of the coil is \( 5 \, \text{A} \cdot \text{m}^2 \).