Ch 8: 5.6.19 Daily Quiz material Flashcards
a device that protects against excess current by flipping open
circuit breaker
a device that protects against excess current by melting
fuse
a way to protect against electric shock
grounding
the difference between the magnetic and geographic poles
magnetic declination
a device that converts electrical energy into kinetic energy
motor
a device that converts kinetic energy into electrical energy
generator
a device that changes the electric potential of electricity
transformer
what are two methods of grounding?
- polarized plug - one prong is bigger; used on smaller appliances
- 3-prong plug w/ a dedicated ground - the dedicated ground is different (cylindrical) from the other prongs; used in larger appliances
of the two types of grounding in plugs, which is better and why?
dedicated ground in a 3-prong plug is better, b/c electricity only flows through when needed
how does an iron nail act like a magnet?
each little spot on the surface of the nail (called a domain) has its own random magnetic orientation. a permanent magnet forces the domains to line up. this is called domain alignment. when the nail is removed from the permanent magnet, the domain becomes random again.
where is the magnetic south pole located?
near, (not at) the geographic north pole
what creates a magnetic field?
an electric current
what creates an electric current?
a moving magnetic field. this is called electromagnetic induction.
diagram of a transformer looks like…
equation: the relationship between electric potential and number of loops, w/r/t transformers
primary potential over primary loops is secondary potential over secondary loops (n = # of loops)
equation: the relationship between current and electric potential, w/r/t transformers
primary current times primary potential equals secondary current times secondary potential
