Transcript Electric Current

Movement of
Electricity
Chapter 7 Section 2
Voltage

Electricity moves from a high voltage to a low
voltage
–
–
Voltage is the push behind the electrons that
cause it to move
Voltage is what packs the punch/jolt felt in an
electrical shock
Flow of electricity
• For electricity to flow you must have a
closed circuit
– A closed circuit is one in which the light is
connected to both ends (pos. and neg.) of the
battery with no break in the wire
• If you followed it like a maze you would end up in
the same position
– An open circuit will not allow the flow of
electricity
Electric Current

Electric current is the flow of electricity
(only happens with a closed circuit)
Electricity is the flow of electrons
 Electric current is measured in amperes

Amperes is the aspect of electricity that is the
most lethal
 Amps tells you how much electricity is actually
going to flow through you

Batteries
Batteries produce electrical energy
Batteries do this by maintaining a voltage
difference
– Having a voltage difference allows the
electrons to flow / provide electrical energy
– PROTONS NEVER MOVE (only electrons)
– battery
Electrical Resistance
 Electrical
resistance is the force that
opposes the flow of electrons
 All materials have some electrical
resistance


Insulators have a lot of electrical resistance
Conductors have a small amount of electrical
resistance
Factors that Affect
Electrical Resistance
 Thickness of a wire
 Skinnier = more resistance
 Fatter = less resistance
 Length
 Longer = more resistance
 Shorter = less resistance
 Temperature
 Hotter = more resistance
 Cooler = less resistance
Transforming Electrical
Energy
• Resistance in wires allows electricity
to be transformed to other forms of
energy
– Examples = Light and thermal energy
Electrical Resistance
and Light Bulbs

A light bulb sends the electricity
through a very thin wire called a
filament


The filament increases electrical resistance
That increase in electrical resistance causes
the electrical energy to be transformed into
light and thermal NRG