Electric Charge Flashcards
what can LEDS be used for in a circuit?
to indicate the presence of a current.
is a series or parallel circuit used in house hold lighting?
parallel because one Light can be turned off at a time instead of having to turn the mall off for at once (series)
what is current?
the rate of flow of charge.
what is electric current in solid metallic conductors?
a flow of negatively charged electrons.
what is voltage?
the energy transferred per unit charge passed.
what is a volt?
a joule per coulomb.
why are metals electric conductors?
they have delocalised electrons in their outer electron shell that free to move throughout the structure and carry charge.
why are plastics insulators?
They do not let electrons flow very easily from one atom to another. The atoms have tightly bound electrons, that are not free to roam around and be shared by neighboring atoms.
can insulating materials be charged by friction?
yes
what happens when an insulator is rubbed? (electrons)
charging by friction occurs, where the insulator may gain or loose electrons. if it gains electrons it becomes negatively charges and if it looses electrons it becomes positively charged.
what forces occur between like and opposite charges?
there are forces of attraction between unlike charges and repulsion between like charges.
what are some potential dangers of electrostatic charges?
static electric charge can build up on tankers as the fuel flows through the pipe ( charging by friction). this could cause a spark that might ignite the fuel vapours and cause an explosion.
what are some uses of electrostatic charges?
SPRAY PAINTING- the positively charges paint droplets attract to the negative object and the drops repel eachother so it results in an even Finnish.
INK JET PRINTERS- Tehran ink droplets are charges and the deflecting plates are also charged oppositly and the voltages accros the plates are varied to aim the ink jet.
