Electromechaincal

4. one polarity of a voltage, current, or charge that has an excess of electrons.
6. the smallest part of a compound that is made of individual atoms
10. an object that moves in two directions
12. the shell in which an electron moves around the nucleus of an atom.
14. This number is equal to the number of protons (positively charged particles) in the nucleus of an atom.
15. one of the three principal parts of an atom. Has a positive charge
16. current that reverses its direction of flow periodically. Reversals generally occur at regular intervals.
18. anything that occupies space.
19. the force that causes one object to push another object away from itself
21. a device or material that permits current to flow through it easily.
22. (1) one of the basic building blocks of nature. An atom is the smallest part of this; (2) one part of a group of devices.

1. an electric charge developed when an object contains more protons than electrons
2. one of the principal parts of an atom. Has no charge and is part of the nucleus
3. a material used to electrically isolate two conductive surfaces.
5. the smallest part of an element that contains all the properties of that element
7. moving in only one direction
8. electrons located in the outer orbit of an atom.
9. a material that contains four valence electrons and is used in the production of solid-state devices.
11. current that does not reverse its direction of flow
13. the force that causes one object to pull another object to itself
17. one of the three major parts of an atom. Carries a negative charge
20. the center or middle