11. Cleats or spikes on shoes make friction because they provide a surface. 12. Rolling friction is than sliding friction. 13. Ball bearings purpose is to create friction. 14. In order for a train to move on the tracks there must be friction between the and the . 15. Heat shields on a space craft are necessary when it reenters the earth’s atmosphere because at the high speed of entry air will . 16. Crickets use friction to . 17. Mucous on slugs is remarkable because it’s both and . 18. When air molecules into each other they cause friction.

answer: its c lololo

layers of the earth affect the waves and these effects are seen on instruiments such as seimometers

it is called kinetic energy

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