In a generator, as the magnet spins, opposite poles of the magnet push the electrons in opposite directions. this back-and-forth movement of electrons is called what?
a) revolutions per minute
b) direct current
c) alternating current .
in contrast, the movement of electrons in one direction in a battery circuit is called what?
a)strength of current
b)direct current
c)alternating current .

Amachinist needs to remove a tight fitting pin of material a from a hole in a block made of material b. the machinist heats both the pin and the block to the same high temperature and removes the pin easily. what statement relates the coefficient of thermal expansion of material a to that of material b? a) the situation is not possible, heating block b will shrink the hole in the material as the material expands with increasing temperatureb) material b has the same coefficient of expansion as does material ac) material b has a negative coefficient of expansion and a has a positive coefficient of expansiond) material a has a greater coefficient of expansion than does material be) material b has a greate

An observer that stands still as the electron moves by him, will observe

According to social exchange theory, altruistic behaviors benefit the individual who performs them. t/f