Download WYSIWYG - DiMaggio

W.Y.S.I.W.Y.G
(What You See Is What You’ll Get)
Unit 2: Forces and Motion
Part 1: Motion
Vocabulary
Motion
Velocity
Relative Motion
Acceleration
Reference Point
Deceleration
Speed
Major Concepts





Motion of an object is always judged in relationship with
another object.
Speed is distance over time.
Velocity is the speed in a given direction.
Acceleration is the rate of change in velocity.
Objects accelerate any time their motion changes(speeding up,
slowing down, OR changing direction.
Formulas
 speed or velocity = distance / time
 acceleration = (final velocity – initial velocity) / time
Part 2: Net Forces
Vocabulary
Force
Net Force
Newton
Balanced Force
Spring Scale
Unbalanced Force
Major Concepts






A force is a push or pull exerted on an object.
Forces are measured in Newtons (N).
Forces have a direction.
Net force is the overall force on an object after all of the forces are added
together.
Balanced forces are equal forces acting on an object in
opposite directions.
Unbalanced forces are unequal net forces that cause a
change in an object’s motion.
S8P3. Students will investigate relationship between force, mass, and the motion of objects.
a. Determine the relationship between velocity and acceleration.
Part 3: Special Forces
Vocabulary
Friction
Static Friction
Rolling Friction
Sliding Friction
Air Resistance
Gravity
Law of Universal Gravitation
Fluid Friction
Major Concepts




Friction is a force that acts against motion when two objects rub
against each other.
The four forms of friction are static, fluid, sliding, and rolling.
A falling object experiences unbalanced force due to gravity.
Gravity is the forces that pull objects toward each other.
 The weight of an object proportional to the amount of gravitational
pull on the object.
 Since the Earth is the most massive object around, gravity pulls
everything toward the center of the Earth.
 The force of gravity proportional to the mass of an object.
 The force we call weight on Earth is equal to an object’s mass times
the acceleration due to gravity (9.8 m/sec2).
 Gravity acts between all objects in the universe.
Formulas
 weight = mass X 9.8 m/s2
Part 4: Laws of Motion
Vocabulary
1st Law of Motion
Inertia
2nd Law of Motion
3rd Law of Motion
Major Concepts



An object will maintain its state of motion unless acted upon by an unbalanced
force, we call this inertia.
The applied force on an object is related to the mass of the
object and its acceleration.
For every action there is an equal yet opposite reaction.
Formulas
 Force = mass X acceleration
S8P3. Students will investigate relationship between force, mass, and the motion of objects.
b. Demonstrate the effect of balanced and unbalanced forces on an object in terms of gravity, inertia, and friction.
c. Demonstrate the effect of simple machines (lever, inclined plane, pulley, wedge, screw, and wheel and axle) on
work.
Part 5: Work and Machines
Vocabulary
Work
Mechanical Advantage
Machine
Efficiency
Input
Joule (J)
Output
Major Concepts
Work is done when three things happen: 1) a force is applied to an object, 2)
the object moves, and 3) the object moves in the direction of the force.
 Work is measured in units called Joules (J).
 Using machines makes work SEEM easier, but does not change the amount of
work that must be done.
 Anything you do is called the INPUT, anything the machine does is called the
OUTPUT
Mechanical Advantage tells how much easier a machine makes a job, and does not
have a unit.
Efficiency tells what percentage of the work you did actually was used to
accomplish the job; the rest of your input work went to overcoming friction.
There are three main types of machines: 1) machines that multiply your input force
(MA > 1), machines that multiply the distance your force is exerted (MA < 1), and
machines that change the direction of your force (MA = 1)
When you use a machine, there is a trade-off between force and distance;
as one goes up, the other goes down.





Formulas
 Work = force x distance
 Mechanical Advantage = Output FORCE / Input FORCE
 Efficiency = Output WORK / Input WORK x 100%
S8P3. Students will investigate relationship between force, mass, and the motion of objects.
b. Demonstrate the effect of balanced and unbalanced forces on an object in terms of gravity, inertia, and friction.
c. Demonstrate the effect of simple machines (lever, inclined plane, pulley, wedge, screw, and wheel and axle) on
work.
Part 6: Simple Machines
Vocabulary
Simple Machine
Fulcrum
Screw
Fixed Pulley
Inclined Plane
1st Class Lever
Wheel and Axle
Pulley System
Wedge
2nd Class Lever
Pulley
Lever
3rd Class Lever
Moveable Pulley
Compound Machine
Major Concepts







Simple machines are machines which can be operated with a single movement.
There are six types of simple machines: inclined plane, wedge, screw, lever, wheel
and axle, and pulley.
Inclined planes, screws, and wedges all allow you to apply less force, but you
have to apply the force over a greater distance. (MA > 1) They are also all
related (all have a slanted surface (inclined plane) part).
o To increase the MA, make the inclined plane part longer.
Levers are classified based on the location of the fulcrum, input, and output.
(MA is >, =, or < 1 depending on arrangement)
o To increase the MA, move the output closer to the fulcrum, and/or the input
farther away from the fulcrum
Pulleys are classified based on if they move with the object or not, and can be
combined into a pulley system. (MA > or = 1, depending on arrangement)
o To increase the MA, add more pulleys or sections of rope.
The MA of a wheel and axle is determined by which part you apply a force
to. If you apply a force to the axle (like in a bicycle), then the machine
increases the distance (MA < 1). If you apply a force to the wheel (like in a
doorknob), then the machine increases the size of the force (MA > 1).
o To increase the MA, make the axle smaller and/or the wheel larger.
Compound machines are created by combining multiple simple machines
together.
Formulas



MA (inclined plane) = length of plane / height of plane
MA (lever) = distance from fulcrum to input / distance from fulcrum to output
MA (pulley) = # of sections of rope supporting load
S8P3. Students will investigate relationship between force, mass, and the motion of objects.
b. Demonstrate the effect of balanced and unbalanced forces on an object in terms of gravity, inertia, and friction.
c. Demonstrate the effect of simple machines (lever, inclined plane, pulley, wedge, screw, and wheel and axle) on
work.