A metallic ring of mass 1 kg has moment of inertia 1 kg m² when rotating about one of its diameters. It is molten and remoulded into a thin uniform disc of the same radius. How much will its moment of inertia be, when rotated about its own
axis.

The moment of inertia of disc about own axis is 1 kg-m².

Explanation:

Given that,

Mass of ring m= 1 kg

Moment of inertia of ring at diameter

The radius of metallic ring and uniform disc both are equal.

So,

We need to calculate the value of radius of ring and disc

Using theorem of perpendicular axes

Put the value into the formula

Put the value of moment of inertia

Put the value of M

So,

We need to calculate the moment of inertia of disc about own axis

Using formula of moment of inertia

Put the value into the formula

Hence, The moment of inertia of disc about own axis is 1 kg-m².

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

it is a negative acceleration