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 Instructional Focus DocumentPhysics
 TITLE : Unit 05: Conservation of Energy SUGGESTED DURATION : 18 days

#### Unit Overview

Introduction

This unit focuses on the properties of and calculations involving energy.

Prior to this Unit

• 6.8A – Compare and contrast potential and kinetic energy
• 6.8E – Investigate how inclined planes can be used to change the amount of force to move an object.
• 6.9C – Demonstrate energy transformations such as energy in a flashlight battery changes from chemical energy to electrical energy to light energy.
• Integrated Physics and Chemistry
• I.5A – Recognize and demonstrate that objects and substances in motion have kinetic energy such as vibration of atoms, water flowing down a stream moving pebbles, and bowling balls knocking down pins.
• I.5B – recognize and demonstrate common forms of potential energy, including gravitational, elastic, and chemical, such as a ball on an inclined plane, springs, and batteries.
• I.5C – Investigate the law of conservation of energy.

During this Unit

Students apply their conceptual understandings of conservation of energy and energy transformations gained in previous science courses and extend those understandings to calculate in various scenarios with given formulas. Students will analyze scenarios, determine the appropriate formula from the large number provided by the teacher (see TEKS specificity for more details), and calculate to determine the desired variable.

After this Unit

Students will recognize energy and related properties in the systems around them and within them. Students will use their understanding of energy to make informed decisions.

Research

”By the end of the 12th grade, students should know that:

• …scientists can bring information, insights, and analytical skills to bear on matters of public concern. Acting in their areas of expertise, scientists can help people understand the likely causes of events and estimate their possible effects.”

 Scientists investigate natural phenomena in order to understand and explain each phenomenon in terms of systems. How are the properties of systems and their components related to their classification? How are the components, processes, and / or patterns of systems interrelated?   Scientific investigation is an orderly process to ensure that scientific claims are credible. Why is credibility so important in the scientific field? How is scientific knowledge generated and validated?   Data is systematically collected, organized, and analyzed in terms of patterns and relationships to develop reasonable explanations and make predictions. What gives meaning to data? What is the value of observing patterns and relationships in data?   Scientists analyze, evaluate, and critique each other’s work using principles of scientific investigations in order to build on one another’s ideas through new investigations. How can we know what to believe about a scientific claim?
Unit Understandings
and Questions
Overarching Concepts
and Unit Concepts
Performance Assessment(s)

Although energy may change form, energy is conserved and can be calculated throughout a mechanical system.

• In what ways can we classify the forms of energy?
• In what ways can we calculate the forms of mechanical energy?
• In what ways do the calculations of mechanical energy reinforce the law of conservation of energy?

Systems

• Energy

Classifications

• Mechanical
• Kinetic
• Potential

Properties

• Work
• Force
• Distance
• Mass
• Acceleration
• Height
• Velocity
• Power
• Time
• Impulse

Patterns

• Relationships between properties of energy

Models

• Work-energy theorem

Constancy

• Conservation of energy

Change

• Energy transformations
 Assessment information provided within the TEKS Resource System are examples that may, or may not, be used by your child’s teacher. In accordance with section 26.006 (2) of the Texas Education Code, "A parent is entitled to review each test administered to the parent’s child after the test is administered." For more information regarding assessments administered to your child, please visit with your child’s teacher.

#### MISCONCEPTIONS / UNDERDEVELOPED CONCEPTS

Misconceptions:

• Students may think energy that leaves a system as heat energy produced by friction is “destroyed”, rather than understanding that energy is still within the universe.
• Students may think that work is done any time a force is applied, rather than understanding that work only occurs if the object moves in the direction in which the force is applied.
• Students may think the work done to lift an object is dependent on the path the object takes, instead of on the final height.

Underdeveloped Concepts:

• Students may think energy and force are the same.

#### Unit Vocabulary

Key Content Vocabulary:

• Conservation of energy – the fundamental principle of physics that the total energy of an isolated system is constant, despite internal changes
• Conservative force – force in which the work done by the force is determined only by the displacement of the mass
• Elastic potential energy – energy related to the stretch or compression of an object
• Gravitational potential energy – energy related to the position of an object
• Kinetic energy – energy of motion
• Mechanical energy – the sum of potential and kinetic energy for an object
• Power – rate at which energy is transformed
• Work – a force applied to an object that results in a displacement in the same direction
• Work-energy theorem – when work is done on an object, the kinetic energy of the object changes

Related Vocabulary:

 Constant Converted Developed Displacement Energy Force Friction Gravity        Heat energy Height Joules Mass Potential energy Stationary Time Velocity Watt
Unit Assessment Items System Resources Other Resources

Show this message:

Unit Assessment Items that have been published by your district may be accessed through Search All Components in the District Resources tab. Assessment items may also be found using the Assessment Center if your district has granted access to that tool.

System Resources may be accessed through Search All Components in the District Resources Tab.

State:

Texas Education Agency – Texas Safety Standards

http://www.tea.state.tx.us/index2.aspx?id=5483 (look under Documents)

Texas Gateway for Online Resources by TEA – Kinetic and Potential Energy

https://www.texasgateway.org/resource/kinetic-and-potential-energy

Texas Gateway for Online Resources by TEA – OnTRACK Scientific Process Skills

https://www.texasgateway.org/binder/ontrack-scientific-process-skills

Texas Gateway for Online Resources by TEA – Power

https://www.texasgateway.org/resource/power

Texas Gateway for Online Resources by TEA – Work-Energy Theorem

https://www.texasgateway.org/resource/work-energy-theorem

General:

Get Your Physics On “Introduction” (Episode 1, Audio Podcast)

https://itunes.apple.com/us/podcast/get-your-physics-on/id628043458?mt=2  (available as a free podcast on iTunes U in the K-12 section under Texas Education)

Get Your Physics On: “Conservation on a Ramp” (Audio Podcast)

https://itunes.apple.com/us/podcast/get-your-physics-on/id628043458?mt=2 (available as a free podcast on iTunes U in the K-12 section under Texas Education)

Get Your Physics On “Getting to Know a Ballistic Pendulum”

https://itunes.apple.com/us/podcast/get-your-physics-on/id628043458?mt=2 (available as a free podcast on iTunes U in the K-12 section under Texas Education)

Texas Regional Collaboratives “Teaching Interactive Physics (TIPs) from the TRC” (Audio podcast)

https://itunes.apple.com/us/itunes-u/teaching-interactive-physics/id625394600 (available as a free subscription found within iTunes U in the K-12 section under Texas Education)

TAUGHT DIRECTLY TEKS

TEKS intended to be explicitly taught in this unit.

TEKS/SE Legend:

• Knowledge and Skills Statements (TEKS) identified by TEA are in italicized, bolded, black text.
• Student Expectations (TEKS) identified by TEA are in bolded, black text.
• Portions of the Student Expectations (TEKS) that are not included in this unit but are taught in previous or future units are indicated by a strike-through.

Specificity Legend:

• Supporting information / clarifications (specificity) written by TEKS Resource System are in blue text.
• Unit-specific clarifications are in italicized, blue text.
• Information from Texas Education Agency (TEA), Texas College and Career Readiness Standards (TxCCRS), and American Association for the Advancement of Science (AAAS) Project 2061 is labeled.
• A Partial Specificity label indicates that a portion of the specificity not aligned to this unit has been removed.
TEKS# SE# TEKS SPECIFICITY
P.1 Scientific processes. The student conducts investigations, for at least 40% of instructional time, using safe, environmentally appropriate, and ethical practices. These investigations must involve actively obtaining and analyzing data with physical equipment, but may also involve experimentation in a simulated environment as well as field observations that extend beyond the classroom. The student is expected to:
P.1A Demonstrate safe practices during laboratory and field investigations.

Demonstrate

SAFE PRACTICES DURING LABORATORY AND FIELD INVESTIGATIONS

Including, but not limited to:

• Following classroom safety guidelines, as outlined in the Texas Education Agency Texas Safety Standards
• Handling and wearing appropriate safety equipment
• Equipment

Note(s):

• TxCCRS:
• I. Nature of Science – C3 – Demonstrate skill in the safe use of a wide variety of apparatuses, equipment, techniques, and procedures.
P.2 Scientific processes. The student uses a systematic approach to answer scientific laboratory and field investigative questions. The student is expected to:
P.2C Know that scientific theories are based on natural and physical phenomena and are capable of being tested by multiple independent researchers. Unlike hypotheses, scientific theories are well established and highly reliable explanations, but may be subject to change.

Know

SCIENTIFIC THEORIES ARE BASED ON NATURAL AND PHYSICAL PHENOMENA AND ARE CAPABLE OF BEING TESTED BY MULTIPLE INDEPENDENT RESEARCHERS

Including, but not limited to:

• Based on natural and physical phenomena
• Capable of being tested by multiple independent researchers
• Well established, highly reliable explanations
• Subject to change as new areas or science and new technologies are developed

Note(s):

• TxCCRS:
• I. Nature of Science – A2 – Use creativity and insight to recognize and describe patterns in natural phenomena.
• I. Nature of Science – A4 – Rely on reproducible observations of empirical evidence when constructing, analyzing, and evaluating explanations of natural events and processes.
P.2D Design and implement investigative procedures, including making observations, asking well defined questions, formulating testable hypotheses, identifying variables, selecting appropriate equipment and technology, evaluating numerical answers for reasonableness, and identifying causes and effects of uncertainties in measured data.

Design, Implement

INVESTIGATIVE PROCEDURES

Including, but not limited to:

• Making observations
• Formulating testable hypotheses
• Identifying variables
• Selecting appropriate equipment and technology
• Evaluating numerical answers for reasonableness
• Identifying causes and effects of uncertainties in measured data
• Instrument errors
• User errors

Note(s):

• TxCCRS:
• I. Nature of Science – A3 – Formulate appropriate questions to test understanding of natural phenomena.
P.2E

Demonstrate the use of course apparatus, equipment, techniques, and procedures, including multimeters (current, voltage, resistance), balances, batteries, dynamics demonstration equipment, collision apparatus, lab masses, magnets, plane mirrors, convex lenses, stopwatches, trajectory apparatus, graph paper, magnetic compasses, protractors, metric rulers, spring scales, thermometers, slinky springs, and/or other equipment and materials that will produce the same results.

Demonstrate

THE USE OF COURSE APPARATUS, EQUIPMENT, TECHNIQUES, AND PROCEDURES

Including, but not limited to:

• Balances
• Dynamics demonstration equipment
• Collision apparatus
• Lab masses
• Stopwatches
• Trajectory apparatus
• Graph paper
• Metric rulers
• Spring scales
• Thermometers
P.2F

Use a wide variety of additional course apparatus, equipment, techniques, materials, and procedures as appropriate such as ripple tank with wave generator, wave motion rope, tuning forks, hand-held visual spectroscopes, discharge tubes with power supply (H, He, Ne, Ar), electromagnetic spectrum charts, laser pointers, micrometer, caliper, computer, data acquisition probes, scientific calculators, graphing technology, electrostatics kits, electroscope, inclined plane, optics bench, optics kit, polarized film, prisms, pulley with table clamp, motion detectors, photogates, friction blocks, ballistic carts or equivalent, resonance tube, stroboscope, resistors, copper wire, switches, iron filings, and/or other equipment and materials that will produce the same results.

Use

A WIDE VARIETY OF ADDITIONAL COURSE APPARATUS, EQUIPMENT, TECHNIQUES, MATERIALS, AND PROCEDURES AS APPROPRIATE

Including, but not limited to:

• Computer
• Data acquisition probes
• Scientific calculators
• Graphing technology
P.2G Make measurements with accuracy and precision and record data using scientific notation and International System (SI) units.

Make

MEASUREMENTS

Including, but not limited to:

• Accuracy
• Precision

Record

DATA

Including, but not limited to:

• Scientific notation
• International System (SI) units
• Significant Digits (TxCCRS)

Note(s):

• TxCCRS:
• II. Foundation Skills: Scientific Applications of Mathematics – A2 – Use exponents and scientific notation.
• II. Foundation Skills: Scientific Applications of Mathematics – F2 – Use appropriate significant digits.
P.2H Organize, evaluate, and make inferences from data, including the use of tables, charts, and graphs.

Organize, Evaluate, Make inferences

DATA

Including, but not limited to:

• Tables
• Charts
• Graphs

Note(s):

• TxCCRS:
• I. Nature of Science – E1 – Use several modes of expression to describe or characterize natural patterns and phenomena. These modes of expression include narrative, numerical, graphical, pictorial, symbolic, and kinesthetic.
P.2I Communicate valid conclusions supported by the data through various methods such as lab reports, labeled drawings, graphic organizers, journals, summaries, oral reports, and technology-based reports.

Communicate

VALID CONCLUSIONS SUPPORTED BY THE DATA

Including, but not limited to:

• Lab reports
• Labeled drawings
• Graphic organizers
• Journals (science notebooks)
• Summaries
• Oral reports
• Technology-based reports

Note(s):

• TxCCRS:
• III. Foundation Skills: Scientific Applications of Communication – A1 – Use correct applications of writing practices in scientific communication.
P.2J Express relationships among physical variables quantitatively, including the use of graphs, charts, and equations.

Express

RELATIONSHIPS AMONG PHYSICAL VARIABLES QUANTITATIVELY

Including, but not limited to:

• Graphs
• Charts
• Equations

Note(s):

• TxCCRS:
• II. Foundation Skills: Scientific Applications of Mathematics – 2B – Carry out formal operations using standard algebraic symbols and formulae.
• VIII. Physics – A4 – Understand the concept of density.
P.3 Scientific processes. The student uses critical thinking, scientific reasoning, and problem solving to make informed decisions within and outside the classroom. The student is expected to:
P.3A Analyze, evaluate, and critique scientific explanations by using empirical evidence, logical reasoning, and experimental and observational testing, so as to encourage critical thinking by the student.

Analyze, Evaluate, Critique

SCIENTIFIC EXPLANATIONS, SO AS TO ENCOURAGE CRITICAL THINKING BY THE STUDENT

Including, but not limited to:

• Use
• Empirical evidence
• Logical reasoning
• Experimental and observational testing

Note(s):

• Project 2061: By the end of the 8th grade, students should know that:
• Scientific knowledge is subject to modification as new information challenges prevailing theories and as a new theory leads to looking at old observations in a new way. 1A/M2
• Some scientific knowledge is very old and yet is still applicable today. 1A/M3
• Scientific investigations usually involve the collection of relevant data, the use of logical reasoning, and the application of imagination in devising hypotheses and explanations to make sense of the collected data. 1B/M1b*
• If more than one variable changes at the same time in an experiment, the outcome of the experiment may not be clearly attributable to any one variable. It may not always be possible to prevent outside variables from influencing an investigation (or even to identify all of the variables). 1B/M2ab
• Project 2061: By the end of the 12th grade, students should know that:
• From time to time, major shifts occur in the scientific view of how things work. More often, however, the changes that take place in the body of scientific knowledge are small modifications of prior knowledge. Continuity and change are persistent features of science. 1A/H2
• TxCCRS:
• I. Nature of Science – A1 – Utilize skepticism, logic, and professional ethics in science.
• I. Nature of Science – A4 – Rely on reproducible observations of empirical evidence when constructing, analyzing, and evaluating explanations of natural events and processes.
P.3B Communicate and apply scientific information extracted from various sources such as current events, news reports, published journal articles, and marketing materials.

Communicate, Apply

SCIENTIFIC INFORMATION EXTRACTED FROM VARIOUS SOURCES

Including, but not limited to:

• Current events
• News reports
• Published journal articles
• Marketing materials
P.3E Express, manipulate, and interpret relationships symbolically in accordance with accepted theories to make predictions and solve problems mathematically.

Express, Manipulate, Interpret

RELATIONSHIPS SYMBOLICALLY IN ACCORDANCE WITH ACCEPTED THEORIES

Including, but not limited to:

• Make predictions
• Solve problems mathematically
• Manipulation of equations algebraically
• Proportional reasoning

Note(s):

• TxCCRS:
• VIII. Physics – B1 – Understand how vectors are used to represent physical quantities.
• VIII. Physics – B2 – Demonstrate knowledge of vector mathematics using a graphical representation.
• VIII. Physics – B3 – Demonstrate knowledge of vector mathematics using a numerical representation.
P.6 Science concepts. Science concepts. The student knows that changes occur within a physical system and applies the laws of conservation of energy and momentum. The student is expected to:
P.6A Investigate and calculate quantities using the work-energy theorem in various situations.

Investigate, Calculate

QUANTITIES USING THE WORK-ENERGY THEOREM IN VARIOUS SITUATIONS

Including, but not limited to:

• The mechanical energy of an object does not change in a frictionless system, but does change in real-world systems
• Recognize situations / examples in which work is being done
• Work in terms of energy transfer using the work-energy theorem (linear systems)
• W = ∆KE
• Work = change in kinetic energy
• W = Fd
• Work = (force)(distance)
• E = Pt
• Energy = (power)(time)
• KE = ½ mv2
• Kinetic energy = ½ (mass)(velocity)2
• Potential energy
• PEgmgh
• Gravitational potential energy = (mass)(acceleration due to gravity)(height)
• PEelastic =  1/2kx2
• Elastic potential energy = ½ (spring constant)(distance stretched or compressed)2
• ME = KE + PE
• Mechanical energy = kinetic energy + potential energy
• The total mechanical energy of an object does not change in a system with only conservative forces
• Conservative force – force in which the work done by the force is determined only by the displacement of the mass
• In real world systems where there are nonconservative forces (e.g., friction, air resistance), the total mechanical energy is not conserved

Note(s):

• The STAAR Physics Reference Materials include the formulas for work and energy as listed above.
• In Grade 6, students compare and contrast kinetic and potential energy (6.8A).
• In Grade 6, students investigate how inclined planes can change the amount of force required to move an object (6.8E).
• TxCCRS:
• VIII. Physics – D1 – Understand potential and kinetic energy.
• VIII. Physics – D2 – Understand conservation of energy.
• VIII. Physics – D3 – Understand the relationship of work and mechanical energy.
P.6B Investigate examples of kinetic and potential energy and their transformations.

Investigate

EXAMPLES OF KINETIC AND POTENTIAL ENERGY AND THEIR TRANSFORMATIONS

Including, but not limited to:

• Types of energy
• Possible examples may include:
• Mechanical
• Chemical
• Solar
• Nuclear
• Thermal
• Electrical
• Transfer of energy in different systems
• Falling bodies
• Roller coasters
• Pendulums
• Spring
• Simple
• Possible additional examples may include:
• Skateboard ramps (U shaped)
• Students releasing objects from specific heights

Note(s):

• In Grade 6, students compare and contrast kinetic and potential energy (6.8A).
• In Grade 6, students demonstrate energy transformations between chemical, mechanical, electrical, light (radiant), thermal and sound (6.9C).
• In Grade 7, students further illustrate energy transformations within organisms (7.7A).
• TxCCRS:
• VIII. Physics – C3 – Understand the concept of momentum.
• VIII. Physics – D1 – Understand potential and kinetic energy.
• VIII. Physics – D2 – Understand conservation of energy.
• VIII. Physics – E4 – Understand angular momentum. [Possible Pre-AP Extension]
P.6C

Calculate the mechanical energy of, power generated within, impulse applied to, and momentum of a physical system.

Calculate

MECHANICAL ENERGY OF, POWER GENERATED WITHIN A PHYSICAL SYSTEM

Including, but not limited to:

• ME = KE + PE
• Mechanical energy = kinetic energy + potential energy
• P = W / t
• Power = work / time

Note(s):

• The STAAR Physics Reference Materials include the formulas for power and mechanical energy, impulse, and momentum as listed above.
• TxCCRS:
• VIII. Physics – C3 – Understand the concept of momentum.
• VIII. Physics – D1 – Understand potential and kinetic energy.
• VIII. Physics – D2 – Understand conservation of energy.
• VIII. Physics – E4 – Understand angular momentum. [Possible Pre-AP Extension]
P.6D

Demonstrate and apply the laws of conservation of energy and conservation of momentum in one dimension.

Demonstrate, Apply

THE LAW OF CONSERVATION OF ENERGY

Including, but not limited to:

• KEi + PEi = KEf + PEf
• Law of conservation of energy
• Conservation of energy in different systems
• Moving objects vs. friction
• Falling bodies
• Roller coasters
• Pendulums
• Spring
• Simple

Note(s):

• The STAAR Physics Reference Materials include the formulas for the law of conservation of energy and the law of conservation of momentum as listed above.
• TxCCRS:
• VIII. Physics – C3 – Understand the concept of momentum.
• VIII. Physics – D1 – Understand potential and kinetic energy.
• VIII. Physics – D2 – Understand conservation of energy.
DEVELOPING TEKS

TEKS that need continued practice, improvement, and refinement, but do not necessarily need to be explicitly taught in this unit.

TEKS/SE Legend:

• Knowledge and Skills Statements (TEKS) identified by TEA are in italicized, bolded, black text.
• Student Expectations (TEKS) identified by TEA are in bolded, black text.
• Portions of the Student Expectations (TEKS) that are not included in this unit but are taught in previous or future units are indicated by a strike-through.

Specificity Legend:

• Supporting information / clarifications (specificity) written by TEKS Resource System are in blue text.
• Unit-specific clarifications are in italicized, blue text.
• Information from Texas Education Agency (TEA), Texas College and Career Readiness Standards (TxCCRS), and American Association for the Advancement of Science (AAAS) Project 2061 is labeled.
TEKS# SE# TEKS SPECIFICITY
P.1 Scientific processes. The student conducts investigations, for at least 40% of instructional time, using safe, environmentally appropriate, and ethical practices. These investigations must involve actively obtaining and analyzing data with physical equipment, but may also involve experimentation in a simulated environment as well as field observations that extend beyond the classroom. The student is expected to:
P.1B Demonstrate an understanding of the use and conservation of resources and the proper disposal or recycling of materials.

Demonstrate

AN UNDERSTANDING OF THE USE AND CONSERVATION OF RESOURCES AND THE DISPOSAL OR RECYCLING OF MATERIALS

Including, but not limited to:

• Use and conservation of resources
• Disposal or recycling of materials
P.2 Scientific processes. The student uses a systematic approach to answer scientific laboratory and field investigative questions. The student is expected to:
P.2A Know the definition of science and understand that it has limitations, as specified in subsection (b)(2) of this section.

Know

THE DEFINITION OF SCIENCE AND UNDERSTAND THAT IT HAS LIMITATIONS

Including, but not limited to:

• Science, as defined by the National Academy of Sciences, is the “use of evidence to construct testable explanations and predictions of natural phenomena, as well as the knowledge generated through this process”.
• …”some questions are outside the realm of science because they deal with phenomena that are not scientifically testable.”
P.2B Know that scientific hypotheses are tentative and testable statements that must be capable of being supported or not supported by observational evidence.

Know

THAT SCIENTIFIC HYPOTHESES ARE TENTATIVE AND TESTABLE STATEMENTS THAT MUST BE CAPABLE OF BEING SUPPORTED OR NOT SUPPORTED BY OBSERVATIONAL EVIDENCE

Including, but not limited to:

• Tentative and testable statements
• Supported or not supported by observational evidence

Note(s):

• TxCCRS Note:
• I. Nature of Science – A3 – Formulate appropriate questions to test understanding of natural phenomena.
• I. Nature of Science – A4 – Rely on reproducible observations of empirical evidence when constructing, analyzing, and evaluating explanations of natural events and processes.
P.3 Scientific processes. The student uses critical thinking, scientific reasoning, and problem solving to make informed decisions within and outside the classroom. The student is expected to:
P.3C Explain the impacts of the scientific contributions of a variety of historical and contemporary scientists on scientific thought and society.

Explain

THE IMPACTS OF SCIENTIFIC CONTRIBUTIONS ON SCIENTIFIC THOUGHT AND SOCIETY

Including, but not limited to:

• Historical and contemporary scientists
• Newton
• Einstein
• Galileo
• Maxwell
• Coulomb
• Ørsted
• Ampere
• Lenz
P.3D Research and describe the connections between physics and future careers.

Research, Describe

THE CONNECTIONS BETWEEN PHYSICS AND FUTURE CAREERS

Including, but not limited to:

• How physics is used in various careers
• Possible examples may include:
• Medical physicist
• Astronomer
• Teacher
• Geophysicist
• Equipment designer
• Telecommunications engineer
• Materials designer
• Engineer
P.4 Science concepts. The student knows and applies the laws governing motion in a variety of situations. The student is expected to:
P.4A Generate and interpret graphs and charts describing different types of motion, including investigations using real-time technology such as motion detectors or photogates.

Generate, Interpret

GRAPHS AND CHARTS DESCRIBING DIFFERENT TYPES OF MOTION

Including, but not limited to:

• Linear motion
• Constant velocity
• Accelerated motion (positive and negative acceleration)
• Information illustrated on graphs
• Position-time
• Distance
• Displacement
• Average velocity
• Describe motion
• Velocity-time
• Displacement
• Instantaneous velocity
• Average velocity
• Acceleration
• Describe motion
• Acceleration-time
• Constant acceleration (no slope)
• Describe motion
• Investigation using real-time technology
• Motion detectors
• Photogates
• Ticker timer

Note(s):

• Students in Grade 6 calculate average speed using distance and time measurements, measure and graph changes in motion, and investigate how inclined planes can be used to change the amount of force to move an object (6.8C, 6.8D).
• Students in Grade 8 differentiate between speed, velocity, and acceleration (8.6B).
• TxCCRS:
• I. Nature of Science – A4 – Rely on reproducible observations of empirical evidence when constructing, analyzing, and evaluating explanations of natural events and processes.
• VIII. Physics – C1 – Understand the fundamental concepts of kinematics.
• VIII. Physics – A1 – Demonstrate familiarity with length scales from sub-atomic particles through macroscopic objects.
P.4B Describe and analyze motion in one dimension using equations and graphical vector addition with the concepts of distance, displacement, speed, average velocity, instantaneous velocity, frames of reference, and acceleration.

Describe, Analyze

MOTION IN ONE DIMENSION

Including, but not limited to:

• Vectors vs. scalars
• Magnitude and direction
• Displacement
• Distance
• Displacement vs. distance
• Velocity vs. speed
• Vector quantities of displacement and vector sum
• Manipulate equations to solve for an unknown
• d = vit + ½a∆t2
• Displacement = (initial velocity)(change in time) + ½ (acceleration)(change in time)2
• vavg = ∆d / ∆t
• Average velocity = displacement / change in time
• Find the average velocity given two or more velocities
• a = (vfvi)  / ∆t
• Acceleration = (final velocity – initial velocity) / change in time
• a = vf2vi2 / 2∆d
• Acceleration = [(final velocity)2 – (initial velocity)2] / [2(displacement)]
• Instantaneous velocity (find initial or final velocity)
• Frames of reference
• Motion with respect to a specified position
• Situations in which velocities add and subtract relative to an observer

Note(s):

• The STAAR Physics Reference Materials include the formulas for average velocity, acceleration, and displacement as listed above.
• Students in Grade 6 calculate average speed using distance and time measurements, measure and graph changes in motion, and investigate how inclined planes can be used to change the amount of force to move an object (6.8C, 6.8D, 6.8E).
• Students in Grade 8 differentiate between speed, velocity, and acceleration (8.6B).
• TxCCRS:
• VIII. Physics – C1 – Understand the fundamental concepts of kinematics.
• VIII. Physics – E1 – Understand rotational kinematics. [Possible Pre-AP Extension]
P.4C Analyze and describe accelerated motion in two dimensions, including using equations, graphical vector addition, and projectile and circular examples.

Analyze, Describe

ACCELERATION MOTION IN TWO DIMENSIONS

Including, but not limited to:

• Projectile motion
• Launched upwards at an angle (conceptual understanding)
• Path of a projectile comparing velocity and acceleration at any point on the path
• Launched horizontally (conceptual understanding and calculations)
• Path of a projectile comparing velocity and acceleration at any point on the path
• Analyze projectile motion in terms of its horizontal and vertical components
• Use data from one of the components to find time and use that value to find the unknown quantity
• Acceleration = (final velocity)– (initial velocity)/ 2 x (displacement)
• a = vfvi2 / 2∆d
• Circular motion
• ac = vt2 / r
• Centripetal acceleration = (tangential velocity)2 / radius
• Direction of acceleration and velocity
• Graphical vector addition in two dimensions
• Pythagorean Theorem
• Sine, cosine, tangent functions

Note(s):

• The STAAR Physics Reference Materials include the formulas for centripetal acceleration as listed above.
• TxCCRS:
• VIII. Physics – C1 – Understand the fundamental concepts of kinematics.
P.4D Calculate the effect of forces on objects, including the law of inertia, the relationship between force and acceleration, and the nature of force pairs between objects using methods, including free-body force diagrams.

Calculate

THE EFFECT OF FORCES ON OBJECTS

Including, but not limited to:

• Net force
• Fnet = ma
• Net force = (mass)(acceleration)
• Relationship between force and acceleration
• Problems involving force, mass, and acceleration using Newton’s 2nd law
• Friction forces
• The differences between friction-free and friction-inclusive systems
• Law of inertia
• The relationship between mass and inertia using Newton’s 1st law
• Nature of force pairs
• Interpreting real-life situations using Newton’s 3rd law
• Nature of force pairs between objects
• Action-reaction pairs
• Problems involving forces on each object
• Mass vs. weight
• Distinguish between mass and weight
• Calculate the weight of an object
• Fnet = ma (a = g)
• Torque
• τ = Fr
• Torque = (force)(lever arm)
• Compare torque to the net force on an object
• Free-body diagrams of force analysis

Note(s):

• The STAAR Physics Reference Materials include the formulas for net force, torque, and acceleration due to gravity as listed above.
• Students are introduced to the concepts of force in Grades 6 and 8 by observing change in the motion of an object that is acted upon by an unbalanced force (6.8B, 8.6A).
• In Grade 6, students investigate how inclined planes can be used to change the force applied to an object (6.8E).
• In Grade 7, students consider how forces affect motion in organisms (7.7B).
• In Grade 8, students are introduced to Newton’s laws of motion (8.6C).
• TxCCRS:
• I. Nature of Science – A2 – Use creativity and insight to recognize and describe patterns in natural phenomena.
• VIII. Physics – A3 – Understand the concepts of mass and inertia.
• VIII. Physics – A5 – Understand the concepts of gravitational force and weight.
• VIII. Physics – C2 – Understand forces and Newton’s laws.
• VIII. Physics – E3 – Apply the concept of static equilibrium. [Possible Pre-AP Extension]