Transcript Chapter 9: Circuits

Integrated Science
Unit 3, Chapter 9
Unit Three: Electricity and Magnetism
Chapter 9 Circuits
9.1
More Electric Circuits
9.2
Series Circuits
9.3
Parallel Circuits
Chapter 9 Learning Goals





Identify a series circuit.
Identify a parallel circuit.
Describe how our houses are wired.
Build series and parallel circuits.
Calculate total resistance in series circuits.

Build circuits with fixed and variable resistors.
 Analyze series circuits using Ohm’s law.
 Use Kirchhoff’s voltage law to find the voltage drop across a circuit
component.
 Compare current in series and parallel circuits.

Compare voltage in series and parallel circuits.
 Use Kirchhoff’s current law to find an unknown current in a parallel
circuit.
 Identify a short circuit.

Explain why a short circuit is dangerous.
Chapter 9 Vocabulary Terms

Kirchhoff’s current law

Kirchhoff’s voltage law

parallel circuit

series circuit

short circuit
9.1 More Electric Circuits
Key Question:
What kinds of electric circuits can you build?
*Read text section 9.1
AFTER Investigation 9.1
9.1 More Electric Circuits

In SERIES circuits, current
can only take one path.

In PARALLEL circuits the
current can take more than
one path.
9.1 What happens if you plug in too
many things?
 You
can use more
current than the wires
can safely hold.
 If
your circuit breaker
"trips", this is a clue
that you should
unplug some
appliances.
9.2 Series Circuits
Key Question:
How do you use Ohm's law in series circuits?
*Read text section 9.2
AFTER Investigation 9.2
9.2 Kirchhoff's Voltage Law
Around any closed circuit, all the voltage
changes must add up to zero.
9.3 Parallel Circuits
Key Question:
How do parallel circuits work?
*Read text section 9.3
AFTER Investigation 9.3
9.3 Kirchhoff's Current Law
The same total current flowing into a branch
point has to flow out again.
9.3 Open circuits and short circuits