You have two cylindrical bar magnets with the same mass, length, and dipole moment, but different moments of inertia, I1 and I2. You place each bar magnet so that it is initially oriented perpendicular to a uniform magnetic field. When you let each bar magnet go from rest, you find that magnet 1 takes less time than magnet 2 to rotate so that it is parallel to the magnetic field. Is I1 greater than, less than, or equal to I2

;   is less than

Explanation:

Firstly, we take a look at the concept of moment of inertia, This concept comes from the fact that it resists change in motion. A body that has a higher value of moment of inertia requires more force ( torque) to change its position as compared to a body with lesser value of moment of inertia.

Now taking a look at the situation in  the question, both the magnets are placed in similar magnetic field, so having the same amount of force, hence torque acts on both magnets.

Since magnet 1 takes less time to rotate compared to magnate 2, hence magnet 1's moment of inertia should be less than that of magnet 2.

Therefore, ;   is less than

no. dot product   =0 when vecs at right angles

electromagnetic shielding is the practice of reducing the electromagnetic field in a space by blocking the field with barriers made of conductive or magnetic materials. shielding is typically applied to enclosures to isolate electrical devices from their surroundings, and to cables to isolate wires from the environment through which the cable runs. electromagnetic shielding that blocks radio frequency electromagnetic radiation is also known as rf shielding.

the shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields. a conductive enclosure used to block electrostatic fields is also known as a faraday cage. the amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic

from wikipedia