Mr. wang works in a recycling center. recyclable materials arrive at the center mixed together. workers use magnets to separate steel cans from other items. which two statements are true about the force between a steel can and a magnet? a. gravity pushes the can toward the magnet. b. the force between the can and the magnet is a noncontact force. c. the attraction between the can and the magnet is a pull. d. the attraction between the can and the magnet is a push.

close lines strong magnet less close weaker

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