TIMMY KEEGAN
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Labs
Containers lab 9/6/18
Buggy Lab 9/19/18
Cart Lab 9/30/18
Newtons Second Law Lab 10/19/18
Impulse Lab
Momentum Lab
Accident Project
Wave on a String Lab
Circuit Lab
Content
Unit 0 - Patterns & measurements
Unit 1 - Kinematics
Unit 2 - Forces
Unit 3 - 2D Motion
Unit 4 - Energy
Unit 5 - Momentum and Impulse
Unit 6 - Rotational motion
Unit 7 - Simple Harmonic Motion
Unit 8 - Waves
Unit 9 - Circuits
Blog Posts
Forces
Requirements for test
Know Newton's First, Second and Third Laws
Be able to create/decipher Force Diagrams and System Schemas
Be able to make Force Calculations
Relating Representations of Motion and Force Models
Solving Problems with Forces and Motion
Definition of force
An interaction between two objects that results in a push or pull
Types of Forces
From onenote
How to Represent Forces
Force Diagram -
Show direction and magnitude of forces acting upon an object
How to draw one
Put a point representing the object
Draw arrows in direction of force
label the forces with force type and objects interacting
System Schemas -
show objects interacting and types of forces
How to draw
Write the name of the object in the center and circle it
Write down the names of the other objects interacting and circle them
Connect the objects interacting with a solid line for contact and dotted line for non contact (gravity)
Label the type of force
Force Tables
used to show strength of forces in each direction
Draw using boxes showing force in Newtons in x and y direction
each force should have 1 x and 1 y box
Newton's First Law
Definition
An object will continue to move at a constant velocity unless it feels an unbalanced push or pull
inertia
an objects resistance to change in motion
the more massive the object, the more inertia
Balanced forces
constant velocity
can be at rest
Unbalanced Forces
Acceleration positive or negative depending on forces
non constant velocity
Newton's Second Law
Definition
Acceleration is directly proportional to total force and inversely proportional to mass
ΣF
=m/a
Newton's Third Law
Definiton
Whenever two objects interact each object exerts an equal force on the other object. These forces are equal in magnitude but opposite in direction
Do not confuse this with 2 equal forces acting upon the same object
Third Law pairs do not cancel out because they are acting upon different objects
Force Calculations
Spring Force
Fs=-k*
Δx
Spring force=-Spring constant*stretch of spring
Gravity
Fg = mg
Force of gravity = Mass * Gravitational Field Strength
Force of Friction
ƒ = µ * Fn
Friction = Coefficient of Friction * Normal Force
Static Friction
Friction when object is not moving, Increases with increase in Fn until it reaches a point it becomes kinetic friction
Kinetic Friction
Friction when object is sliding, stays constant, less than static friction's highest values
Solving Force Problems
Steps
Draw a Force diagram and Force Table
Put all known values in the Force Table
Write out the equation needed to solve the problem
plug in values and solve
Motion and Forces
Constant 0 Net Force
Constant Velocity
Constant non zero Net Force
constant acceleration
Changing Net Force
Changing Acceleration
They are Directly related
F=ma
Force=Mass*acceleration
Relating Models For Both
Motion
Position time graphs
Velocity time graphs
Acceleration time graphs
Forces
System Schemas
Force Diagrams
Comparison
Motion models are more exact
Solving Problems with Forces and Motion
Relate the 2 using f=ma
If constant Velocity all forces must be balanced
Draw a force table to make sure they are balanced
Plug in Values and solve
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Home
About
Labs
Containers lab 9/6/18
Buggy Lab 9/19/18
Cart Lab 9/30/18
Newtons Second Law Lab 10/19/18
Impulse Lab
Momentum Lab
Accident Project
Wave on a String Lab
Circuit Lab
Content
Unit 0 - Patterns & measurements
Unit 1 - Kinematics
Unit 2 - Forces
Unit 3 - 2D Motion
Unit 4 - Energy
Unit 5 - Momentum and Impulse
Unit 6 - Rotational motion
Unit 7 - Simple Harmonic Motion
Unit 8 - Waves
Unit 9 - Circuits
Blog Posts