historical, standardized model
Conventional current
flow of positive charge
from the positive (+) terminal to the negative (-)
electric current
negatively charged
electrons through a conductor, from a negative (-) to a positive
(+) area, forming electric current
Electron flow
the movement of electric charge through
a conductor, measured as the rate of charge passing a point
per second
Electric current
measure of the opposition to current flow in an
electrical circuit
measured in ohms, symbolized by the Greek
letter omega (Ω)
HAS 2 CATEGORY
Resistance
-Conductors
-Insulators
Factors that Affect Resistance
-Length(high L,high R)
-cross-sectional area (1/A high, R less)
-temp(highT,HighR)
-Kind material(depend on material)
material’s inherent opposition to current
flow.
Resistivity (ρ)
measure of the ability of the material to
conduct an electrical current.
Conductivity (σ)
voltage across a conductor is directly proportional to the
current flowing through it, provided temperature and other
physical conditions remain constant.
OHM’S LAW
Energy provided by a source to move a unit
of charge, from negative to positive
terminal.
Electromotive Force (EMF)
Energy used or dissipated by a unit of charge as it moves between two points in a circuit.
Potential Difference (PD)
Power supplied by
source:
𝑷 =𝓔I
Power dissipated in
resistor:
𝑷 =𝑰^𝟐𝑹
DEVICES FOR MEASURING CURRENT AND VOLTAGE
- device use to measure current
Ammeter
DEVICES FOR MEASURING CURRENT AND VOLTAGE
- device use to measure voltage
Voltmeter
