Unit 1 Measurement and Symbolic Representation1单元的测量和号化的表达.docVIP

Unit 1: Measurement and Symbolic Representation Time Frame: three weeks Activity 1: Practicing Math Operations (SI GLE: 5; PS GLEs: 4, 5) A pretest to assess the students’ math skills and weaknesses is an ideal way to begin this activity. The teacher can then present example problems and then give students practice problems using scientific notation, significant digits, dimensional analysis, metric conversions, relative and percent error and graphical analysis of data. Direct instruction and demonstrations can be provided as needed. Problems may be assigned from the physics textbook or the teacher may wish to generate a set of problems based on student need or provide problems from a workbook. Activity 1: No specialized equipment needed. Unit 1: Measurement and Symbolic Representation Time Frame: three weeks Activity 2: Density of Marbles and Volume of the Textbook (SI GLE: 5; PS GLE: 1) The purpose of this activity is to learn or review the use of precision and accuracy in measurement, to relate precision to significant figures, and to relate accuracy to relative and percent error. These skills should be used throughout the course. Working in pairs, ask students to determine experimentally the density of a group of marbles (or any other small objects of the same composition) using water displacement to find the volume of the marbles, a balance to find their mass, and a metric ruler to measure the length, width and height of the textbook. After data has been collected and calculations have been made, have students share data and results as a class. Discuss the results in terms of precision of the measuring devices used. Stress that the precision of the measuring devices must be reflected in the number of significant digits recorded in the data table and the final calculated answers. Discuss how relative and percent error may be calculated. Remind students that units must be manipulated along with numbers. Students should come up with the suggestion that an average