Highly Recommended
Like all our Science Reasoning Center activities, the completion of the Universal Gravitation activity requires that a student use provided information about a phenomenon, experiment, or data presentation to answer questions. When needed (e.g., on the second activity), this information is accessible within the activity and can often be accessed by tapping on the thumbnail of the Asset panel on the lower right-side of the interactive area.

### The Standards

This NGSS-inspired Universal Gravitation task consists of three activities. Each activity involves a different type of skill or understanding. Collectively, these three activities were designed to address the following NGSS performance expectation:

HS-PS2-4:
Use mathematical representations of Newton's Law of Gravitation to describe and predict the gravitational forces between objects.

As a whole, the questions in this task address a wide collection of disciplinary core idea (DCI), crosscutting concepts (CCC), and science and engineering practices (SEP). There are three activities, each of which involves some form of quantitative description or numerical manipulation. That is, the task of completing each activity requires that the student utilize at least two of the three dimensions of the NGSS science standards - a DCI, a CCC, and/or an SEP.

The following DCI, SEPs, and CCCs are addressed at some point within Universal Gravitation:

DCI:  PS2.B: Types of Interactions
• Newton's law of universal gravitation and Coulomb's law provide the mathematical models to describe and predict the effects of gravitational and electrostatic forces between distant objects.
• Forces at a distance are explained by fields (gravitational, electric, and magnetic) permeating space that can transfer energy through space. Magnets or electric currents cause magnetic fields; electric charges or changing magnetic fields cause electric fields.

SEP 5.2: Using Mathematical and Computational Thinking
Create and/or revise a computational model or simulation of a phenomenon, designed device, process, or system.

CCC 1.1:  Patterns
Different patterns may be observed at each of the scales at which a system is studied and can provide evidence for causality in explanations of phenomena.

CCC 3.2:  Scale, Proportion, and Quantity
Algebraic thinking is used to examine scientific data and predict the effect of a change in one variable on another (e.g., linear growth vs. exponential growth).

Here is our NGSS-based analysis of each individual activity of the Universal Gravitation Science Reasoning task. The core ideas, crosscutting concepts, and science and engineering practices that we reference in our analysis are numbered for convenience. You can cross-reference the specific notations that we have used with the listings found on the following pages:

#### Part 1: Describing the Gravity of the Situation

This activity involves the completion of a short paragraph with 11 missing blanks. A word bank is used to fill in the missing blanks of the paragraph. Students must accurately complete the paragraph before being rewarded the trophy for this activity.

NGSS Claim StatementUse mathematical representations of Newton’s Law of Universal Gravitation to describe the gravitational force between objects.

 Target DCI(s) Target SEP(s) Target CCC(s) Physical Science Motion and Stability: Forces and Interactions HS-PS2.B Newton's law of universal gravitation and Coulomb's law provide the mathematical models to describe and predict the effects of gravitational and electrostatic forces between distant objects. Using Mathematics and Computational Thinking SEP 5.2 Create and/or revise a computational model or simulation of a phenomenon, designed device, process, or system. Pattern s CCC 1.1 Different patterns may be observed at each of the scales at which a system is studied and can provide evidence for causality in explanations of phenomena.

This activity consists of 3 numerical response questions, each of which utilizes randomly-generated numerical quantities. Students must think proportionally in order to determine a new gravitational force value that results when there is a two-fold, three-fold, or even four-fold change in the mass and/or the separation distance. Students must show expertise on each question before being rewarded the trophy for this activity. When they miss a question, they will have to answer a similar question (with different numbers) twice in a row before demonstrating expertise.

NGSS Claim StatementUse mathematical representations of Newton’s Law of Universal Gravitation to describe and predict the value of the gravitational force between objects.

 Target DCI(s) Target SEP(s) Target CCC(s) Physical Science Motion and Stability: Forces and Interactions HS-PS2.B Newton's law of universal gravitation and Coulomb's law provide the mathematical models to describe and predict the effects of gravitational and electrostatic forces between distant objects. Using Mathematical and Computational Thinking  SEP 5.2 Use mathematical or computational representations of phenomena to describe explanations. Scale, Proportion, and Quantity CCC 3.2 Algebraic thinking is used to examine scientific data and predict the effect of a change in one variable on another (e.g., linear growth vs. exponential growth).

#### Part 3: Table Completion

This activity consists of a six-row table with five missing cell values; numerical values are randomized. Students must perform calculations and accurately complete the table before being rewarded the trophy for this activity. Feedback to students inputted values is immediate (once the Check Answers button is used) and they will have opportunity to correct wrongly-inputted values. Once all missing cell values are accurately determined, students earn the Trophy for the activity.

NGSS Claim StatementUse mathematical representations of Newton’s Law of Universal Gravitation to predict the effect of a change in a variable on the gravitational force between objects.

 Target DCI(s) Target SEP(s) Target CCC(s) Physical Science Motion and Stability: Forces and Interactions HS-PS2.B Newton's law of universal gravitation and Coulomb's law provide the mathematical models to describe and predict the effects of gravitational and electrostatic forces between distant objects. Using Mathematical and Computational Thinking SEP 5.2 Use mathematical or computational representations of phenomena to describe explanations. Scale, Proportion, and Quantity  CCC 3.2 Algebraic thinking is used to examine scientific data and predict the effect of a change in one variable on another (e.g., linear growth vs. exponential growth).

#### View: Science and Engineering Practices || Crosscutting Concepts

Complementary and Similar Resources
The following resources at The Physics Classroom website complement the Universal Gravitation Science Reasoning Activity. Teachers may find them useful for supporting students and/or as components of lesson plans and unit plans.

Physics Classroom Tutorial, Circular and Satellite Motion Chapter: Newton's Law of Universal Gravitation

Physics Video Tutorial, Circular and Satellite Motion: Universal Gravitation

Physics Interactives, Circular Motion and Gravitation: Gravitation Simulation

Concept Builders, Circular Motion and Gravitation Chapter, Universal Gravitation

Minds On Physics, Circular Motion and Gravitation Module, Mission CG6: Universal Gravitation

The Calculator Pad, Circular Motion Chapter, Problem Sets CG9 - CG12