Electrics Flashcards
What is electricity?
the flow of charge.
What is the difference between conductors and insulators?
conductors have lots of free to move electrons, insulators don’t
What is current?
the rate of flow of charge
What is 1 amp in terms of Coulobms?
1 coulomb per second
What equation links charge, current and time?
I=Q/T
What is the equation linking current and drift velocity?
I=nAve
I=current
v=drift velocity
A= cross sectional area
n=change density, the number of free electrons that can move per M cubed
What is voltage?
The force that moves charge
What is the electromotive force?
voltage provided by power supplies
What is potential difference?
voltage used up as current flows
What is resistance?
the opposition to the flow of current, defined a R=V/I
How to calculate total resistance in series?
add the resistance together
How to calculate the total resistance in parallel?
add the 1/resistance together, the flip the sum of that
What is ohms law?
current through a conductor is directly proportional to the potential difference across it, provided temperature remains the same.
What is the equation for resistivity?
p=RA/L
Resistivity=resistance x area / length
What is a capacitor?
two metal parallel metal plates that can be charged
Why use a cell over a capacitor?
the cell can hold and provide more charge then the capacitor can
What is the unit of capacitance?
Farold (F)
What happens when a current flows through an inductor?
it creates a magnetic field
What do inductors do to the current?
Inductors smooth out the Change in current
What is the unit of inductance?
Henry, H
