Description:

The task assesses students' understanding of scientific inquiry including the following skills: observation, background research, scientific procedures (including investigation design, measurement techniques, and error analysis), data collection, data display, scientific questions, formulating a hypothesis, measurement skills.

This task is designed to take students approximately 3-6 class periods.

Overall Task Content Area:

Physical Science

Specific Knowledge Areas:

Performance Expectations:

• conducting investigations
• using equipment
• gathering, organizing, and representing data
• formulating conclusions from investigational data

National Science Education Standards:

12 A SI 1: Abilities necessary to do scientific inquiry: Grades 9-12

1.1 Identify questions and concepts that guide scientific investigations. Students should form a testable hypothesis and demonstrate the logical connections between the scientific concepts guiding a hypothesis and the design of an experiment. They should demonstrate appropriate procedures, a knowledge base, and conceptual understanding of scientific investigations.

1.2 Design and conduct scientific investigations. Designing and conducting a scientific investigation requires introduction to the major concepts in the area being investigated, proper equipment, safety precautions, assistance with methodological problems, recommendations for use of technologies, clarification of ideas that guide the inquiry, and scientific knowledge obtained from sources other than the actual investigation. The investigation may also require student clarification of the question, method, controls, and variables; student organization and display of data; student revision of methods and explanations; and a public presentation of the results with a critical response from peers. Regardless of the scientific investigation performed, students must use evidence, apply logic, and construct an argument for their proposed explanations.

1.3 Use technology and mathematics to improve investigations and communications. A variety of technologies, such as hand tools, measuring instruments, and calculators, should be an integral component of scientific investigations. The use of computers for the collection, analysis, and display of data is also a part of this standard. Mathematics plays an essential role in all aspects of an inquiry. For example, measurement is used for posing questions, formulas are used for developing explanations, and charts and graphs are used for communicating results.

1.4 Formulate and revise scientific explanations and models using logic and evidence. Student inquiries should culminate in formulating an explanation or model. Models should be physical, conceptual, and mathematical. In the process of answering the questions, the students should engage in discussions and arguments that result in the revision of their explanations. These discussions should be based on scientific knowledge, the use of logic, and evidence from their investigation.

12 B PS 4: Motions and Forces: Grades 9-12

4.1 Objects change their motion only when a net force is applied. Laws of motion are used to calculate precisely the effects of forces on the motion of objects. The magnitude of the change in motion can be calculated using the relationship F=ma, which is independent of the nature of the force. Whenever one object exerts force on another, a force equal in magnitude and opposite in direction is exerted on the first object.

(Use the "hot" link on the PALS home page to check the full text of related National Science Education Standards, if desired.)

General Instructions to the Teacher:

This task is designed to take students approximately 3-6 class periods.

Students should be ready to work as soon as periods begin. A central supply area, if needed, should be easily accessible. All supplies should be clearly labeled.

Materials for "Friction Force":

The student will need:

• objects-bricks, dynamics carts, cardboard boxes
• springs or other force probes
• boards to drag objects on
• variety of surface types
• lubricants

Advance Preparation:

"What factors affect the amount of friction that an object has?" Is a general question that a teacher could pose to the class. After some discussion, a possible question might be: "What is the relationship between the contact surface area of different sized pieces of cardboard and the friction force of the cardboard."

(Note: Have the students focus on only one factor that affects friction.)

Safety:

• Be careful.
• Teachers and students should always exercise appropriate safety precautions and utilize appropriate laboratory safety procedures and equipment when working on science performance tasks.

Extensions/modifications:

• N/A