Students will understand the following:

Provide the following materials for each group.


Adaptations for Older Students: Challenge students to express the results of their experiments in mathematical terms. 

You can evaluate your students on their experiments using the following threepoint rubric:

Electric Power: Extending the Gradient Concept to a New Context The gradients (or slopes) of graph lines can generally describe the rate of change of any variable plotted on a yaxis with respect to the change in a related variable plotted on the xaxis. Speed and acceleration are only two of the many kinds of rates that can be determined in this way. Ask your students to use the gradient concept to answer the following questions in a totally different context: The power (P) that we buy from our local electric company is defined as the rate of change of energy (E) with respect to a change in time (T). How many kilowatts of power, therefore, are needed to run your hair dryer if it uses energy at a rate suggested by the following set of data: (E1 = 150 j, T1 = 30 sec), (E2 = 300 j, T2 = 60 sec), (E3 = 450 j, T3 = 90 sec), (E4 = 600 j, T4 = 120 sec), and (E5 = 750 j, T5 = 150 sec). Students should use these figures to create a graph with energy (E) represented on the yaxis and time (T) represented on the xaxis. Then they should calculate the gradient of the resulting line to determine the power (P). Note: Power is measured in kilowatts, energy in joules (j), and time in seconds (sec). Defining Terms Have your students write definitions for the following terms and explain how they are related to each other: acceleration, constant speed, terminal speed, balanced forces, unbalanced forces, force, opposing force. 
Experiments with Motion Robert Gardner. Enslow, 1995. Easytodo experiments better illustrate the text and allow a student to understand Newton's Laws of Motion and their application to space flight as well as to the movement of animals and vehicles. Diagrams, explicit lists of materials needed, answers to puzzles, and a bibliography contribute to the usefulness of this work. Mechanics Fundamentals Robert W. Wood. Learning Triangle Press/McGrawHill, 1996. Important principles of physics, specifically relating to the effect of forces on objects at rest or in motion, are explained through the simpletoperform experiments in this book. Line drawings illustrate all experiments and a glossary explains new terms. 
Describing Motion with Position vs. Time Graphs Tom Henderson's physics students at Glenbrook High School, have access to some of the best physics curriculum on the web. Your students are invited to learn about kinematics through the analysis of Position to Time graphs with this excellent example of a multimedia and interactive physics text. Describing Motion with Velocity vs. Time Graphs The next step to understanding the study of moving things ("kinematics") is a tour of the chapter on Velocity to Time graphs at Tom Henderson's multimedia physics text web site. Virtual Motion Graphs Lab An interactive virtual graphing lab includes a printable guide that allows the student to vary the magnitude and direction of velocity data and instantly see what happens to the shapes of the position to time and acceleration to time graphs. Free Body Diagrams or FBD's Learn to predict whether or not a body will move with constant velocity or acceleration, by constructing Free Body Diagrams that identify of all the forces acting on the body and their net effect on motion. 
Click on any of the vocabulary words below to hear them pronounced and used in a sentence.
Context: A car will accelerate when the forces propelling it forward are stronger than the forces attempting to slow it down.
Context: On a distanceversustime graph for a moving object, the gradient is equal to the speed of the object.
Context: The motion of a car can be represented on a graph with position plotted on the yaxis and time on the xaxis.
Context: Not long after she jumped out of the airplane, the skydiver reached her terminal speed. 
This lesson plan may be used to address the academic standards listed below. These standards are drawn from Content Knowledge: A Compendium of Standards and Benchmarks for K12 Education: 2nd Edition and have been provided courtesy of theMidcontinent Research for Education and Learningin Aurora, Colorado. Grade level: 68, 912 Subject area: science Standard: Understands motion and the principles that explain it. Benchmarks: Benchmark 68: Knows that an object's motion can be described and represented graphically according to its position, direction of motion, and speed. Benchmark 68: Understands effects of balanced and unbalanced forces on an object's motion (e.g., 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 such as friction will cause changes in the speed or direction on an object's motion). Benchmark 912: Knows that laws of motion can be used to determine the effects of forces on the motion of objects. Grade level: 912 Subject area: mathematics Standard: Understands and applies basic and advanced properties of functions and algebra. Benchmarks: Understands properties of graphs and the relationship between a graph and its corresponding expression (e.g., maximum and minimum points). Grade level: 912 Subject area: mathematics Standard: Understands and applies basic and advanced properties of the concepts of measurement. Benchmarks: Solves problems involving rate as a measure (e.g., velocity, acceleration). Grade level: 912 Subject area: mathematics Standard: Understands and applies basic and advanced properties of the concepts of geometry. Benchmarks: Uses synthetic (i.e., pictorial) representations and analytic (i.e., coordinate) methods to solve problems involving symmetry and transformations of figures (e.g., problems involving distance, midpoint, and slope; determination of symmetry with respect to a point or line). 
Ted Latham, physics and science/technology teacher, Watchung Hills Regional High School, Warren, New Jersey. 