Transcript “Mu of the Shoe”

“Mu of the Shoe”
Friction: Day 2
Curriculum
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Big Idea: All forces arise from the interactions between
different objects.
Concept: When two surfaces of objects are in contact with
each other, the force of friction between them depends on the
nature of the materials in contact and the normal force.
Competency: Construct a free body diagram indicating the
magnitude and direction of the forces on an object and use
information from the diagram to determine the motion of the
object.
PA Standard 3.2.10.B1: Analyze the relationships among the net
force acting on a body, the mass of the body, and the resulting
acceleration using Newton’s Second Law of Motion.
Today’s Agenda - Academic
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Opener – What is friction?
Go over your reflection responses
(homework).
Define Physics Words. (in the packet)
Free Body Diagrams and friction
Closure: Say one thing that you have
learned in the two lessons on friction.
Honors Goals
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Design an experiment and
conduct an experiment to
compare the amount of friction
between different surfaces.
Solve real world problems with
friction using Newton’s Second
Law:
Fnet = m×a
Today’s Agenda - Honors
Opener – Read the Furniture Company Scenario and your
Materials List as a class. Individually, write down your ideas to
solve the problem. Discuss your ideas in small groups and as
a class.
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As a class, design an experiment to determine the coefficients
of friction between the three available surfaces and the lab
tables.
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Go over friction problems (homework).
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Define the Physics Words, and answer the reflection
questions. (see packet)
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Closure: Say one thing that you have learned in the two
lessons on friction.
Take Home Assignment: Complete the friction scenario handout
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Scenario
A new furniture company in Haverford
Township is asking for your help in
determining the best of three materials to
use on the bottom of their dining room
chairs. The company wants the chairs to
have the least possible amount of friction
when slid across a dining room floor. The
dining room floor surface is the same as
your lab table surface.
Materials for Each Group
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1 felt pasco slider
1 cork pasco slider
1 plastic pasco slider
1 spring scales
a set of masses
clean lab tables
friction scenarios and free body diagram
handouts
Physics Words
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Force of Friction: a force that slows objects
down
Normal Force: Force of a surface on an
object. Always perpendicular to the surface
Force to Slide: Force required to slide the
object at a constant speed (equal to the force
of friction).
Weight: Force of gravity on an object