Download Circuits PPT 2 - Batesville Community School

Concept Summary
Batesville High School Physics
Circuit Schematics
 A schematic
diagram is a symbolic
representation of a circuit.
A
symbol represents each item in the
circuit
 Lines represent wires (paths for charges).
Circuit Symbols

Three Types of Circuits
 Series
 Parallel
 Compound
Series Circuits
 Series
circuits have 1 path for charges
to flow.
Series Circuits
 Voltage
may be different across
different objects in a series circuit.
 Sum of the individual voltages = source
voltage
 Current is the same in all parts of a
series circuit.
 If one “goes out”, they all “go out”
Parallel Circuits
 A parallel
circuit has two or more paths
for charges to move.
Parallel Circuits
 Voltage
is the same across each
element in a parallel circuit.
 Current may vary through different
elements in a parallel circuit.
 Sum of the individual currents = source
current.
 If one “goes out”, the other “stays lit”.
Compound Circuits
 A compound
circuit has both series and
parallel parts.
Adding Resistance in Series
 When
you add resistance in series:
Total resistance increases
 Current decreases

Equivalent Series Circuits
 Rseries
= R1 + R2
Adding Resistance in Parallel
 When
 Total
you add resistance in parallel:
resistance decreases
 Current increases
Equivalent Parallel Circuits
Household Circuits
 Household
circuits are:
parallel circuits
 Typically designed to carry 15 Amperes of
current - maximum.

Overloading Circuits
 Since
adding resistance to a parallel
circuit causes current to increase,
adding appliances to a household circuit
causes current in the house wiring to
increase.
 This means wires must dissipate more
heat energy (P = I2R).
Short Circuits
 A short
circuit is a very low resistance
path in a circuit.
 A short circuit will also cause large
amounts of current to flow in a circuit
and overload the circuit.
Fuses & Circuit Breakers
 Fuses
and circuit breakers act as
automatic switches in a circuit to
prevent dangerous currents from
flowing.
The End