Unit 5: Currents, Circuits, and Magnetism Flashcards
battery
an energy storage device that provides a constant potential difference (6V) between two locations (terminals) inside the battery
Current (I)
the flow of electric charge
convention system for current refers to positive charge, moving
Which way do electrons travel in a battery?
positive terminal to the negative (opposite of usual)
How does a battery work?
- voltage is created when positive and negative charges are separated.
- batteries are charged escalators that move positive charge from the negative terminal to the positive terminal
- ## the battery is a source of voltage because the chemical reactions give potential energy to charge
Drift Velocity
electrons move slowly in the direction opposite of the electric field.
Direct Current (DC)
charge that moves in one direction only (battery)
Alternating Current (AC)
the voltage alternates from positive to negative so the output current from the generator changes its direction at regular intervals
- Charge that repeatedly reverses direction
Resistance (R)
the opposition to motion of charge (current) through a conductor
Factors that affect resistance (4)
-cross-sectional area
-material
-temperature
-length
Greater area/ thicker, (less/more) resistance
less resistance
copper, (less/more) resistance
less resistance
Iron, (less/more) resistance
more resistance
low temperature, (less/more) resistance
less resistance
high temperature, (less/more) resistance
more resistance
shorter wire length, (less/more) resistance
less resistance
longer wire length, (less/more) resistance
more resistance
Electric Power (P)
the rate at which electrical energy is converted into non electrical forces of energy like heat or light
(rate at which work is done)
-also known as wattage.
Electric Circuit
path through which charges can flow (bulbs, wires, resistors, batteries)
Open Circuit
no complete path -> no charge flow -> no current