Transcript DO NOW

PHYSICS
ELECTRICITY
Mr. BALDWIN
April 4, 2016
AIM: How do we determine the equivalent
resistance in series circuits?
DO NOW:
• Calculate the resistance of a filament in a
lightbulb that carries a 400mA current when
connected to a 9.0 V battery?
HOME WORK
BALDWIN
1
Resistors in Series
A series connection has a single path from
the battery, through each circuit element in
turn, then back to the battery.
Resistors in Series
The current through each resistor is the same;
the voltage depends on the resistance. The
sum of the voltage drops across the resistors
equals the battery voltage.
Resistors in Series
From this we get the equivalent resistance (that
single resistance that gives the same current in
the circuit).
PHYSICS
ELECTRICITY
Mr. BALDWIN
13 March 2013
AIM: How do we
determine the
equivalent resistance in
parallel circuits?
DO NOW QUIZ: Determine
a. the equivalent resistance in
the circuit
b. the current in the circuit
c. the voltage drop across
each resistor
BALDWIN
5
Resistors in Parallel
A parallel connection splits the current; the voltage
across each resistor is the same:
Resistors in Parallel
The total current is the sum of the currents across
each resistor:
Resistors in Parallel
This gives the reciprocal of the equivalent
resistance:
PHYSICS
ELECTRICITY
Mr. BALDWIN
March 14, 2013
AIM: How do we measure voltage and
current in simple circuits?
DO NOW:
Calculate the equivalent resistance of the circuit?
BALDWIN
HOME WORK – handout
9
Ammeters and Voltmeters
• An ammeter measures current;
• A voltmeter measures voltage.
• An ohmmeter measures resistance; it requires a
battery to provide a current.
Section
22.1
Diagramming Circuits
An ammeter measures the current through a
circuit component.
The same current going through the component
must go through the ammeter, so there can be
only one current path.
A connection with
only one current
path is called a
series connection.
Section
22.1
Diagramming Circuits
Any time the current has two
or more paths to follow, the
connection is labeled parallel.
The potential difference across the
voltmeter is equal to the potential
difference across the circuit
element.
PHYSICS
ELECTRICITY
Mr. BALDWIN
27-Apr-10
AIM: Solving problems involving complex circuits?
DO NOW:
Calculate the equivalent resistance of the circuit?
HOME WORK – READ Chapter 36. Prep for QUIZ
BALDWIN
13
Recall: The same current passes
through all the components;
the sum of the potential drop
across each component is
equal to the potential of the
source
Recall: The potential
across each component
is equal to the potential
of the source, the sum
of the current across
each component is
equal to the current in
the circuit.
Consider the following diagram. Calculate:
a. the equivalent resistance of the resistor combination
b. the current in the circuit
c. the potential drop across each resistor
d. the power dissipated across each resistor
Draw the table in your notebook, perform the
calculations and Fill in the spaces
Check Yourself!
Consider the following diagram. Calculate:
a. the equivalent resistance of the resistor combination
b. the current in the circuit
c. the potential drop across each resistor
d. the power dissipated across each resistor
Draw the table in your notebook, perform the
calculations and Fill in the spaces
Check Yourself!
PHYSICS
ELECTRICITY
Mr. BALDWIN
4 May, 2010
AIM: How do we solve compound circuits?
DO NOW: Write down the formulas for the
following:
a. Ohm’s law
b. Resistors in Series
• c. Resistors in parallel
• d. Power (in terms of I, V and R)
HOME WORK – DO TEXT pg 561: # 29 & 31
TEXT pg. 575. REVIEW QUESTIONS 1 - 10
BALDWIN
21
COMBINATION CIRCUIT