Science
SCI.IV.3.2
Grade: 6
Strand IV:
Using Scientific Knowledge in Physical Science
Standard 3:
Motion of Objects - All students will describe how things around us
move, explain why things move as they do, and demonstrate and explain
how we control the motion of objects
Benchmark 2:
Relate motions of objects to unbalanced forces in two dimensions.
Reflecting and Constructing:
SCI.I.1.1 - Generate scientific questions about the world based on observation.
SCI.I.1.2 - Design and conduct scientific investigations.
SCI.I.1.3 - Use tools and equipment appropriate to scientific investigations.
SCI.I.1.4 - Use metric measurement devices to provide consistency in an investigation.
SCI.I.1.5 - Use sources of information in support of scientific investigations.
SCI.I.1.6 - Write and follow procedures in the form of step-by-step instructions, formulas, flow diagrams, and sketches.
SCI.II.1.2 - Describe limitations in personal knowledge.
SCI.II.1.3 - Show how common themes of science, mathematics, and technology apply in real-world contexts.
Vocabulary / Key Concepts
Context
Changes in motion and common forces:
• speeding up
• slowing down
• turning
• push
• pull
• friction
• gravity
• magnets
Changing the direction:
• changing the direction of a billiard ball
• bus turning a corner
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
Changing the speed:
• car speeding up
• rolling ball slowing down
• magnets changing the motion of
objects
• walking
• swimming
• jumping
• rocket motion
• objects resting on a table
• tug-of-war
Knowledge and Skills
Benchmark Clarification:
Motion can be described in terms of balanced and
unbalanced forces.
Students will explain the motion of objects due to
balanced or unbalanced forces, and demonstrate
examples of each.
Balanced forces occur when an object is at rest or
when an object is in motion at a constant speed
and direction. When an object sits motionless on a
table the forces acting on the object are balanced.
The force of the object against the table (action) is
equal to the force of the table pushing up on the
object (reaction). When a car travels at a constant
speed, the forward force of the car is equal to the
frictional forces acting on the car.
Resources
Coloma Resources:
Motion, Forces & Energy (Prentice Hall)
Chapters 1 & 2
See LABS. Newton’s Law & Washers
Science Challenge (attached).
Other Resources:
• Science Explosion
•
Bill Nye: Gravity, Friction
•
Curious Kids Museum- Simple Machines
•
Michigan Teacher Network Resources
•
The Exploratorium – Sport Science
Unbalanced forces cause an object to change
direction or speed. When a car speeds up the
forces are unbalanced because the forward force
acting on the car is greater than the frictional forces
pushing back on the car.
•
Roller Coaster Physics – entire online book
of applied physics including lessons, labs,
and prep. Outstanding.
•
Discovery Online – Build Your Own Coaster
Buoyant force is the upward push of a fluid (gas or
liquid) on an object.
•
Discovery Channel Feature – Thrill Rides
•
Scope Unit – Forces and Motion
Videoconferences Available
For more information, see
www.remc11.k12.mi.us/dl or call Janine Lim
471-7725x101 or email jlim@remc11.k12.mi.us
IV.3.MS.2
• Motion Mania from COSI Toledo
• Roller Coaster Science from COSI Toledo
• Physics Rules from the Louisville Science
Center
• Propulsion from NASA Glenn Research
Center
• Rocket Science from the Discovery Center
of Springfield
6th Grade Science Curriculum
Technology Resources
IV.3.MS.2 Relate motions of objects to
unbalanced forces in two dimensions.
Vernier Probes available: Force Sensor,
Motion Detector, Rotary Motion Sensor
Instruction
Benchmark Question: How do forces affect the motion
of an object?
Assessment
Coloma Required Assessment:
Focus Question: How can the motion of objects be
affected by balanced and unbalanced forces?
Forces Project (attached)
Thread a string at least five meters long through a
drinking straw and tie the string between two chairs that
are set at least four meters apart so that the string is
taut. Then inflate a balloon (“hotdog” type balloons work
best) and twist and hold the end to keep it inflated (do
not tie). Then attach the balloon with tape to the drinking
straw with the twisted end closest to one chair. When
releasing the balloon, the teacher will ask students,
“What started the balloon moving?” and “What
happened as the balloon was released?” Using the
terms “balanced” and “unbalanced forces,” students will
explain the motion of the balloon. Discussion should
include the terms found in the Key Concepts.
Optional Assessment:
Draw a picture of 2 teams of students playing
tug-of-war. Using the words balanced forces,
unbalanced forces, and motion, explain what
happens when the tug-of-war teams both pull
away from each other but there is no
movement. Use arrows on the diagram to
represent the forces of both teams. Using the
words balanced forces, unbalanced forces, and
motion, describe what needs to happen for one
team to be the winner of the tug-of-war.
(Give students rubric before activity.)
Students should be able to set up their own
investigations and write formal lab reports for the
second activity. The teacher will give each small group a
wooden block with a sturdy eye hook on two opposite
ends, two spring scales, and a flat surface to work on.
Students will design and carry out an investigation to
determine the effects of balanced and unbalanced
forces on the motion of the block. Students will record
data. Each student will write a lab report describing the
investigation. Each student will discuss their results
using the terms in the Key Concepts.
Students should have access to reference materials that
could assist them in their investigation design (e.g.,
encyclopedias, science textbooks, etc.).
Scoring Rubric
Criteria: Accuracy of description-forces in
no movement situation:
Basic - Identifies no balanced forces and
incorrectly or incompletely draws force arrows
on diagram.
Apprentice - Identifies both of the balanced
forces and incorrectly or incompletely draws
force arrows on diagram.
Meets - Identifies both balanced forces and
correctly draws force arrows on diagram.
Exceeds - Provides clear and complete
identification of balanced forces and correctly
draws force arrows on diagram.
Criteria: Accuracy of description-forces in
winning situation:
Basic - Identifies none of the unbalanced
forces and incorrectly or incompletely draws
force arrow on diagram.
Apprentice - Identifies both of the
unbalanced forces and incorrectly or
incompletely draws force arrow on diagram.
Meets - Identifies both of the unbalanced
forces and correctly draws force arrow on
diagram.
Exceeds - Provides clear and complete
identification of unbalanced forces and
correctly draws force arrow on diagram.
Teacher Notes:
“The motion of an object can be described by its position, direction of motion, and speed. That motion can be
measured and represented on a graph. An object that is not being subjected to a[n unbalanced] force will
continue to move at a constant speed and in a straight line. If more than one force acts on an object along a
straight line, then the forces will reinforce or cancel one another, depending on their direction and magnitude.
Unbalanced forces will cause changes in the speed or direction of an object’s motion.” (NSES)
Focus Questions
• What does force do to an object?
• Can a force be acting on an object that is at rest (or moving with a constant speed in a straight line)?
Notes
Students (and most adults) often believe that an object stops moving if there is no force on it. In fact, a force is
needed to stop an object as well as start its motion. Students also tend to believe that an object sitting on a
table (for example) has no force acting on it because it is not moving. The force of gravity is acting on it, as it
acts on all objects near the Earth’s surface, but because the object is not moving there must be an equal and
opposite force pushing up on it to balance the force of gravity. This upward force is the “reaction” to the
downward force of gravity – these balanced forces are “interaction forces.”