Magnetic moment = I × A

As per the relation suggests up if the bar magnet is cut into two equal pats it's length gets halved up i.e l/2 nd so does will the area of cross section will get halved up ..

So as a result of it pole strength will also get halved up nd henceforth will be the magnetic moment too get halved i.e M/ 2 .....

Answer:

Introduction:
In this question, we are given a bar magnet of magnetic moment M and length l which is cut into two equal parts each of length l/2. We have to find the magnetic moment of each part.

Magnetic Moment:
The magnetic moment (M) of a magnet is defined as the product of its magnetic pole strength (m) and the distance (2l) between the two poles. Thus, we can write,

M = m × 2l

where m is the magnetic pole strength and 2l is the distance between the two poles.

Division of Magnet:
Now, the given magnet is cut into two equal parts each of length l/2. Let's assume that the magnetic pole strength of each part is m1 and m2, and their respective distances between the poles are 2l1 and 2l2.

Thus, we can write,

M = m1 × 2l1 = m2 × 2l2

Since the magnet is cut into two equal parts, their magnetic pole strengths will also be equal i.e. m1 = m2.

Also, the distance between the poles of each part will be half of the original distance i.e. l1 = l2 = l/2.

Substituting these values in the above equation, we get

M = m1 × l = m2 × l
or m1 = m2 = M/l

Therefore, the magnetic moment of each part will be M/l.

Conclusion:
In conclusion, we can say that if a bar magnet of magnetic moment M and length l is cut into two equal parts each of length l/2, then the magnetic moment of each part will be M/l.