Electricity Flashcards
current is measured in…
amperes (A)
current calculation when time and charge are involved?
current = charge/time
I = Q/t
Q is measured in coulombs (C)
t is measured in seconds (s)
I is measured current
current is measured with a
ammeter
potential difference is measured in?
volts
calculation of potential difference
V = E/Q
what is potential difference measured with?
voltmeter
a voltmeter is placed in a parallel or series?
parallel
a ammeter is placed in a series or parallel circuit?
series
resistance is measured in what?
ohms
ohmic conductor
resistor at a constant temp
non-ohmic conductor
filament lamp
does filament lamp current and temperature decrease or increase
increase
what does is mean when electrons and ions vibrate more and collide more mean?
increase resistance
how many loops are in a series current?
one loop
in a series circuit the potential difference is what?
shared across each component
parallel components are connected to the power supply in
separate branches
the current in a parallel circuit is what?
shared
the potential difference in a parallel circuit is the…
same across every branch
hazards of electricity (6)
damage insulation
electric shock
fire hazard
overheating cables
melting
damp conditions
a fuse is a thin piece of wire which will melt if?
current is too high
earth wires what so a current can flow?
safe route
why do earth wires have a low resistance
so strong current surges through which break the fuse and disconnect
energy is measured in
joules
power of a component is measured in
watt
direct currents
flow in one direction
alternate currents
current changes direction
charge is measured in
coulombs
protons have a charge of?
+1
electrons have a charge of?
-1
neutrons have a charge of?
0
electrostatic charge can build up due to friction. the clouds discharge through the air to earth. this results to?
lightening
damages of electrostatic charges include
- electric shock
- sparks
