Levers & Pulleys
Investigation 3
Part 1
One-Pulley Systems
Students discover two ways to set up a one-pulley system to lift a load: 1) single fixed pulley and 2) single movable pulley. They use a spring scale to quantify and compare the effort needed to lift the load in each of the two systems.
3. Lesson set up and Management
1. Systems
- 1.2 Structure of Systems
- 1.2.1 Systems Approach
Describe how the parts of a system interact and influence each other.
(ST01, STI02, STI03, & STI04) - 1.3 Changes in Systems
- 1.3.1 Nature of Forces
Know the factors that determine the strength and interactions of the various forces.
(CH01 1.3.1)
2. Inquiry
- 2.1 Investigating Systems
- 2.1.1 Questioning
Generate questions that can be answered through scientific investigations.
(IN01 2.1.1) - 2.1.4 Modeling
Correlate models of the behavior of objects, events, or processes to the behavior of the actual things under investigation; test models by predicting and observing actual behaviors or processes.
(IN04 2.1.4)
A single pulley can be set up in two ways, fixed or movable.
A single movable pulley can lift a load using half as much force as can a single fixed pulley.
A single fixed pulley gives the advantage of change in direction.
3. Lesson set up and Management
Materials:
Make an overhead of the Pulley Diagram.
Student Management:
Have student(s) sort materials or make a materials list on the board; have one person from each pair gather the materials.
Specific students can be designated as “materials persons”.
Be sure to inspect pulleys for accuracy and set scales to zero.
Review the use of scales with students.
Make overhead transparencies of all Student Work Sheets to aid in review and discussion.
Read Teacher and Student background sections before doing the investigations.
Writing:
Write about Sparky and his troop.
Research Block and Tackle.
Write a story about how the pulley got its name.
Reading:
See Pulleys in the FOSS manual’s Science Stories Folio.