At the beginning of a unit on forces, Ms. Alton is leading a class discussion asking her students what they know about forces. Below is a list of the ideas brought up by her class.

I. A force is a push or pull on an object.
II. The amount of force an object has depends on its size.
III. Forces have both a strength and direction.
IV. When two objects collide, the force of one object is transferred to the second object.
V. A moving object stops when its force is used up.
VI. There are no forces on an object that is not moving.
Which of these student responses would you consider to be correct?
For each that is incorrect, what is incorrect about it?

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