Section 2 Flashcards
schematic drawings flashcards are on quizlet
resistance
measure of how difficult it is for electrons to flow through a substance
measured in OHMS (Ω).
current
A steady flow of charged particles
voltage
how much energy each electron carries
It is SUPPLIED BY A SOURCE
measured in VOLTS (V)
amperage
the rate that the electrical current is flowing
measured in AMPS (A)
ohms law
if you increase the voltage in a circuit, the current also increases
if the voltage stays the same, if resistance increases, current decreases
More resistance means more electrons are getting “trapped”, so less are making it through (less current)
formula
Voltage, current, resistance
V
__
I|R
IxR = V
V/I = R
V/R = I
voltemeter/millivoltmeter
voltemeter: measures volts
millivoltmeter: measures really small volts
ammeters/galvanometers
ammeters: measures current
galvanometers: measures small currents
multimeters
measure current, voltage, resistance
2 types of resistors
Wire-wound resistors
Carbon-composition resistors
wire-wound resistors
a wire made of heat-resistance alloy wrapped around an insulating core
longer=more distance to cover
longer and thinner the wire, the higher the resistance
thinner = harder to squeeze through
longer = more distance to cover through a resistor
carbon-composition resistors
made of carbon mixed with other materials.
The carbon mixture is moulded into a cylinder with a wire at each end
changing the size and composition of the cylinder, the resistance can be anywhere from 10 Ω to 20 MΩ
