Additional copies of the Conference Handout may be Obtained at:

http://www.ScienceScene.com (The MAPs Co.)

Dr. M. H. Suckley & Mr. P. A. KlozikEmail: MAP@ScienceScene.com

MAP

Team

MotionA Teacher Designed Unit Based Upon the Michigan Benchmarks

I. Introduction 4

II. Michigan Benchmarks4

III. Unit Objectives5

IV. Prerequisite Skills and Formative Evaluation5

V. Instructional Unit6

VI. Summative Evaluation21

forces

V = d / t

Prerequisite

Skill

II. Michigan Benchmarks for Motion

1. Describe or compare motions of common objects in terms of speed and direction.

Key concepts: Words--east, west, north, south, right, left, up, down. Speed words--fast, slow, faster, slower.

Real- world contexts: Motions of familiar objects in two dimensions, including rolling or thrown balls, wheeled vehicles, sliding objects.

2. Describe how forces (pushes or pulls) are needed to speed up, slow down, stop, or change the direction of a moving object.

Key concepts: Changes in motion--speeding up, slowing down, turning. Common forces--push, pull, friction, gravity. Size of change is related to strength of push or pull.

Real- world contexts: Playing ball, moving chairs, sliding objects.

3. Qualitative describe and compare motion in two dimensions.

Key concepts: Two- dimensional motion--up, down, curved path. Speed, direction, change in speed, change in direction.

Real- world contexts: Objects in motion, such as thrown balls, roller coasters, cars on hills, airplanes.

4. Relate motion of objects to unbalanced and balanced forces in two dimensions.

Key concepts: Changes in motion and common forces--speeding up, slowing down, turning, push, pull, friction, gravity, magnets. Constant motion and balanced forces. Additional forces--attraction, repulsion, action/ reaction pair (interaction force), buoyant force. Size of change is related to strength of unbalanced force and mass of object.

Real- world contexts: Changing the direction--changing the direction of a billiard ball, bus turning a corner; changing the speed--car speeding up, a rolling ball slowing down, magnets changing the motion of objects, walking, swimming, jumping, rocket motion, objects resting on a table, tug- of- war.

5. Design strategies for moving objects by application of forces, including the use of simple machines.

Real- world contexts: Changing the direction--changing the direction of a billiard ball, bus turning a corner; changing the speed--car speeding up, a rolling ball slowing down, magnets changing the motion of objects, walking, swimming, jumping, rocket motion, objects resting on a table, tug- of- war.

F = m x a

11

Future

Unit

III. Unit Objectives for Motion

1. Given the following list of terms, identify each term's correct definition. Conversely, given the definition, identify the correct term.

acceleration, constant acceleration, force, inertia, kinetic energy, linear motion, mass, momentum, speed, time, velocity, weight,

2. Describe how forces (pushes or pulls) are needed to speed up, slow down, stop, or change the direction of a moving object by:

3. Describe and compare motion in two dimensions. Given the distance (x), the time (t) and the formula v = x / t, calculate the speed (v) of any object moving in a straight line with constant velocity. (Newton's First Law)

4. Relate motion of objects to unbalanced forces in two dimensions. (Newton’s Second Law)

a. Given the formula f = m x a, calculate the force acting on an object with a mass (m), moving with a constant acceleration (a).

b. Given the formula a = (vfinal - vinitial) / time, compute the acceleration of an object moving in a straight line with constant acceleration.

5. Relate motion of objects to balanced forces in two dimensions. Given an object at rest or in motion identify the forces acting on the object. (Newton's third Law of Motion.)

5

IV. Prerequisite Skills (skills learners must posses to be successful)

1. Linear measurement skills

2. Use of a stopwatch

3. Computational skills

4. Recording data

5. Cooperative work skills

6. Verbal Skills

7. Communication

8. Reading comprehension

8

Formative Evaluation (Determining if the learner is being successful along the way)

Observation of group interaction

Instructor questions directed to individual students

Ongoing review of data obtained though experimentation

Summative Evaluation (Determining How Successful the Learner has been Mastering the Unit)

Laboratory Report

Comprehensive exam essay forced answer (multiple choice, fill in the blank)

2

V. Instructional Unit

A. Forces 1. Finding the Forces 6

2. Types of Force10

B. Motion in two dimensions – (Newton’s 1st )12

1. Observing Motion13

2. Inertia - Fundamentals14

C. Motion - unbalanced forces in two dimensions (Newton’s 2nd) 15

1. Observing Acceleration16

2. The affect of Mass on Acceleration 17

D. Motion - balanced forces in two dimensions (Newton’s 3rd ) 18

1. Equal and Opposite19

2. Equal and Opposite another Look2020

Finding The Forces Activities

1. Have someone hold a 500-gram hooked mass (HM) in their outstretched hand. Use the arrows so indicate all the forces acting on the HM.

2. Hang the hooked mass from a rubber band. Use the arrows to indicate the forces acting on the HM.

3. Hang the hooked mass from a string. Release the string to drop the HM. (Please catch it.’)

4. Place the HM on a platform spring scale.

5. Place the hooked mass on a soft sponge or piece of foam rubber. The sponge should be soft and about the size of the HM. Push the HM with a horizontal force. The force you apply should be large enough to affect the sponge, but not so large as to make the sponge or the HM slide.

6. Place a coin at the edge of the table. Give it a flick with your finger so it hits the floor some distance away. Make a free-body diagram showing the forces acting on the coin (1) setting on the table, (2) while your finger is in the process of flicking it and (3) while it is moving through the air.

7. Out of a 3 x 5 card, make a device that allows you to flick one coin at the same time that you simply drop a second coin.

6

1. 2.3.

4.5.

6.

7.

8

1.2. 3.

4.

5.

6.

7.

Finding The Forces Activities

Finding The Forces

1. At Rest 2. At Rest 3. Acceleration 4. At Rest

7

5. At Rest 7. Accelerating6. At Rest and Accelerating

Types of Forces

A force is defined as any push or pull that results in accelerating motion

Circular - When objects move in circles, a force acts with a direction that is toward the center of the circle. We call this direction CENTRIPETAL

Gravitational - All objects attract all other objects with a force called gravitational force.

Electromagnetic - Electric forces act on objects when the object carries a net electric charge or a non-uniform distribution of charge. Magnetic force is also observed around a moving electric charge and act on those charges. Physicists believe that all magnetic forces are produced by moving charges.

Frictional - Frictional forces are often classified as sliding, rolling, static and fluid.Sliding and rolling frictional forces result when solids in contact pass by each other. Static frictional force results when solids are in contact, at rest and when a force or forces are trying to cause them to move with respect to each other. Fluid frictional force results when a solid is moving through a gas or a liquid.

Normal - “Normal” means “perpendicular to”. Whenever an object is placed on a surface, a force acts normal to the surfaces in contact. This causes the supporting surface to sag. Since this sagging is slight, it often goes unnoticed. However, it is always there and the resulting force of the surface attempting to return to its original position is perpendicular to the surface.

Tension - Tension force is the force exerted by a string, spring, beam or other object which is being stretched compressed. The electric forces among the molecules give rise to the force.

Circular

Gravitational

Electromagnetic

Frictional

Normal

Tension

7

Newton’s First Law

An object stays at rest or continues to move in a straight line at a constant speed unless acted on by a force.

V = d / t

Observing Motion

1.09.3500.320.320.320.31

1.14.5000.440.430.440.43

VelocityMeters/sec

V = d / t

Distancemeters

AverageSec.

Trial 3Sec.

Trial 2Sec.

Trial 1Sec.

Finish Point Starting Point

.50-meters

t0t1

Equipment Set-Up

6

Time

Distance

Jump

2

1

0

Time

• The interval between two events.

S

T

A

R

T

S

T

O

P

1

00 00 0000 03 25

0

Distance• The interval between two objects.

S

T

A

R

T

S

T

O

P 0

Inertia

Applying Small Force Applying Large Force2Jump

What is Inertia?

Answer:

The tendency of matter to remain at rest if it

is at rest or, if moving, the tendency to keep

moving in the same direction unless acted

upon by some outside force.

20

Newton’s Second Law

When a force acts on a moving object, it will accelerate in the direction of the force dependent on its mass and the force.

F = m x a

Observing Acceleration - of a Toy Car

0.12

.73-m/s/s

.73-m/s2

0.22-sec

0.16-m/s

(8) a = acceleration between points a = v / t

(7) T = change in time between adjacent velocity t = TB – TA 

(6) v = change in adjacent velocity v= v2 – v1 

Position B TB = (t2 + t1) / 2

0.38-sec

Position ATA = (t1 + t0) /2

0.16-sec6) Time (when average velocity occurred)

V2 (.150/.12)

1.25-m/s

V1 (.350/.32)

1.09-m/s(5) Average velocity v = d / t

0.440.32(4) Average Time

0.110.430.32 Third time trial

0.130.440.31 Second time trial

0.110.430.32 First time trial

0.150-m

t1→ t2 (t2- t1)

0.500-m

t0→ t2

0.350-m

t0→ t1

Starting PointAB

t0t1t2

.350-meter.150-meter

.500-meter

13

The Affect of Mass on Acceleration

1.09.5000.320.320.320.31

1.14.5000.440.430.440.43

VelocityMeters/sec

Distancemeters

AverageSec.

Trial 3Sec.

Trial 2Sec.

Trial 1Sec.

With

Without

Battery

8

Newton’s Third Law

Every Action Has An Equal And

Opposite Reaction.

f1 = f2

Newton’s Third Law

Slippery Plastic

Equal and Opposite

1. Crumple the plastic until it looks very wrinkled

2. Place the slippery plastic on a solid, flat surface.

3. Place the car on top on the slippery plastic.

4. Start the car and observe the car and the slippery plastic.

4

Equal and Opposite, Another Look

1. Place two soda cans on a flat surface approximately 25-cm apart.

2. Place the plastic on top of the soda cans.

3. Place the car on top on the plastic as shown.

4. Start the car and carefully observe the car and the plastic.

3

Summative Evaluation

The Class Debriefing - Did we Get There?

If we did

1. The Laboratory Report

2. The Exam

3, Celebration

If we did not

1. Re-teach

2. Provide alternate activities

3. Retest

The Stopwatch

We Had A Great Time