Magnets/electricity Flashcards
what’s a fundamental force
electromagnetism
coulombs law
1/4 x pi x E(o) // q1 x q2 /r2
E(o)
8.85 x 10(-12)
what’s potential difference
difference between highs and lows, its voltage, units volts
where does electric current flow?
from high potential to low
why does current flow?
electric potential
what’s current?
flow of charged particles, from high to low, positive to negative, units amps
current equation
current= charge/time
D.C
straight line, one direction, low power, small devices, most devices use this
charge units
coloumbs
A.C
wiggly line, both directions, large devices, can start current in unconnected circuits, long distance
what’s a conductor
impedes current flow
what’s a superconductor
doesn’t impede current flow
resistance/conductor equation
resistance = voltage/current
if you double the conductor you …
double resistance
resistivity equation
resistance= resistance of material x length/area
resistance units
ohms
metal/wood resistance
metal is low, wood is high
most conductive metal
silver
what’s electron drift
current flows and electrons just drift, 1mm/sec
resistor in series
r= r1 +r2+ r3
resistor in parallel series
r= 1/r1 + 1/r2 + 1/r3
power equation
power = voltage x current
power units
watts/joules per sec
