This resource is explicitly designed to build towards this science and engineering practice.
Comments about Including the Science and Engineering Practice
This Practice pertains primarily to Activity 1: “Pendulum Potential and Kinetic Energy”, which commences on Page 3 of the Supplemental Worksheet. In this exercise, students view automatically-generated bar graphs of Kinetic Energy, Potential Energy, and Total Energy, which are displayed in real time alongside the moving simulation of the child on a swing. They can very clearly see the changes in kinetic and potential energy, which are dependent on the position of the swing in its path of periodic motion. At the top of the swing motion, potential energy is greatest. At the bottom (mid-point on the simulation) kinetic energy is greatest. At any point in the motion, the kinetic energy plus potential energy will equal the total energy of the system. This is important because it’s a way to visualize conservation of energy in a system (a way to “see” what we cannot see). KEY TAKEAWAY: In the moving pendulum system, energy is constantly being converted between kinetic and potential, but the total energy of the system is unchanged. You can see this because the graph of total energy always stays at the same amount. Energy is conserved.
This resource is explicitly designed to build towards this science and engineering practice.
Comments about Including the Science and Engineering Practice
This Practice pertains to Activity 2: “Mechanical Energy in a Pendulum”, which commences on Page 10 of the Supplemental Worksheet. In this exercise, students specifically use simple algebra to calculate the mass of an object on a swing from data on height and speed (given in the simulation). Algebraic expressions pertaining to the Earth’s gravitational constant, the Kinetic Energy formula, and the Potential Energy formula will be used to perform the calculations. The Kinetic Energy formula (½ mass times velocity squared) correlates explicitly with Disciplinary Core Idea MS-PS3.B.1 (see below). By including the Supplementary Worksheet Activity 2, teachers are able to quickly and easily introduce a lesson that integrates quantitative reasoning.