Question

A straight magnetic strip has a magnetic moment of \( 44 \, \text{A m}^2 \). If the strip is bent in a semicircular shape, its magnetic moment will be \( \dots \) A m\(^2\). \[ \text{(Given } \pi = \frac{22}{7} \text{)} \]

Answer 1

Correct Answer: 28

Given: The magnetic moment of the straight strip is $44 \, \mathrm{Am}^2$.  The strip is bent into a semicircular shape. 
When a straight magnetic strip is bent into a semicircular shape, the magnetic moment changes based on the geometry. The formula for the magnetic moment $M$ of a circular loop is given by: 
\[ M = I \times A, \] 
where $I$ is the current and $A$ is the area of the loop. For a semicircular loop, the area is half of the area of a full circle. 

The magnetic moment $M'$ after bending is: 
\[ M' = \frac{M}{2}. \] 

So, the magnetic moment after bending the strip into a semicircular shape is: 
\[ M' = \frac{44}{2} = 28 \, \mathrm{Am}^2. \]
Thus, the correct answer is 28.