Current and Charge Flashcards
Kirtchoffs first law
Sum of current into a junction is equal to current out
The number density of a material
Is the number of free electrons per cubic metric (how good a conductor is it)
If a wire is made thicker how will this effect the mean sift velocity
It slows the mean diff velocity as the particles aren’t tunnelled :directed as much
Define one volt
V= W/Q
The of pd across a component when 1 house is transferred per coulomb
Define one ohm
The resistance of a component when one volt is needed to move one amp of current through it
Ohms law
Voltage and current are directly proportional for a metallic conductor at constant temp
Which of these are ohmic?
Resistor
Filament
Diodes (LED)
Resistor
What Negative temperature coefficient?
Thermistor as it acts weird and resistance decreases with heat
Define resistivity
The product of the resistance and the cross sectional area or a component made of the given material dived by its length
Kirtchoffs evening law
In a closed loop the sum of the emf equals the sum of the pd
Define a progressive wave
An oscillation that travels transferring energy
Define a longitudinal wave
A wave that the transfer of energy is parallel to direction of motion
Transverse wave
The oscillations are perpendicular to the direction of energy transfer
