Download Wet-Cell Batteries - Greenbush Middle River

Chapter 6 / Section 2
ELECTRIC CURRENT
Section 2: Electric Current
An electric current is a flow of electric charge.
Essential Questions
When and how does a voltage difference produce an electric current?
How do batteries produce a voltage difference in a circuit?
How does Ohm’s law relate current, voltage difference, and resistance?
Copyright © McGraw-Hill Education
Electric Current
Electric Current
Electric Current
The flow of electric charge.
Electric Current
The flow of electric charge.
Net movement of electric charges in a
SINGLE DIRECTION.
Electric Current
The flow of electric charge.
Net movement of electric charges in a
SINGLE DIRECTION.
Measured in Amperes (A)
Electric Current
The flow of electric charge.
Net movement of electric charges in a
SINGLE DIRECTION.
Measured in Amperes (A)
Voltage Difference
Relates to the force that causes
electric charges to flow.
Electric Current moves from higher
voltage to lower voltage.
Electric Circuits
Electric Circuits
A closed path that
electric current
follows.
If the circuit is
broken, there is no
current.
Batteries
Supply voltage difference to keep
current flowing in a circuit.
Batteries
Supply voltage difference to keep
current flowing in a circuit.
Dry Cell: (paste)chemical reaction
occurs to cause voltage difference
(common battery)
Wet Cell: (liquid) Car Battery
Dry-Cell Batteries
A cell consists of two electrodes
surrounded by a material called an
electrolyte.
The electrolyte enables charges to
move from one electrode to the
other.
One electrode is the carbon rod,
and the other is the zinc container.
The electrolyte is a moist paste
containing several chemicals.
The cell is called a dry cell because
the electrolyte is a moist paste, and
not a liquid solution.
Copyright © McGraw-Hill Education
Electric Current
Wet-Cell Batteries
A wet cell contains two connected
plates made of different metals or
metallic compounds in a
conducting solution.
A wet-cell battery contains
several wet cells connected
together.
Copyright © McGraw-Hill Education
Electric Current
Outlets
There are 120 V of
difference between the
two slots in an outlet.
The voltage difference
that runs or charges your
devices.
Resistance
Resistance
A resistor resists energy flow and
converts it into other forms of energy,
such as thermal.
Resistance is measured in ohms (Ω).
Resistance
A resistor resists energy flow and
converts it into other forms of energy,
such as thermal.
Resistance is measured in ohms (Ω).
Ohm’s Law
Ohm's law measures the resistance of objects and
materials.
If I stands for the electric current, Ohm's law can be
written as the following equation:
Copyright © McGraw-Hill Education
Electric Current
AC/DC
AC= Alternating Current.
Used in US Households
DC = Direct Current.
Battery-powered devices, such as
flashlights, use direct current.
Review
Electric Current
Voltage Difference
Batteries
Resistance / Resistors
Ohm’s Law
AC/DC
What current runs American Households?