An annihilator is a nonzero density distribution that produces no external field for a particular source geometry. the annihilator describes quantitatively the non-uniqueness of potential field data because any amount of the annihilator can be added to a possible solution without affecting the field of the source. find a simple annihilator (rho) for a spherical mass of radius (a) as viewed from outside the sphere. let rho represent density contrast so that rho can reach negative values.

question1

1,000 tons

question2

3: 8

question 3

store d

step-by-step explanation:

reserve is the answer

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

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