Zip Line Physics A Challenge Based Design Unit Curt Blimline Williamsburg High School CEEMS is funded by the National Science Foundation, grant # 1102990.

Big Idea Human Safety While transporting humans and cargo During relaxation and enjoyment experiences

What factors contribute to the safety and enjoyment of zip line rides? Essential Question What factors contribute to the safety and enjoyment of zip line rides?

The Challenge Design a zip ride trolley system with a braking mechanism that delivers a safe and smooth ride on a test zip line.

Guiding Questions 1. What are the components of a zip line system? 2. What are zip lines used for? 3. What design characteristics contribute to the smoothness of the ride? 4. How do you brake a zip line trolley?

Guiding Questions 5. How do you determine the safety of your design? 6. What forces exist in zip lines? 7. How does friction affect the design of a zip line?

ACS A (real world Application) – Safe and healthy physical activities C (career connections) – Careers affected include mechanical, structural, and materials engineering S (societal impact) – Safe zip lines creates healthy exercise alternatives as well as effective cargo transportation for remotely accessible areas

Standards ONLS Air Resistance and Drag Friction Forces in two dimensions Adding vector forces Motion down inclines

Standards NGSS HS-PS2-1. Analyze data to support the claim that Newton’s second law of motion describes the mathematical relationship among the net force on a macroscopic object, its mass, and its acceleration. HS-ETS1-2. Design a solution to a complex real-world problem by breaking it down into smaller, more manageable problems that can be solved through engineering. HS-ETS1-3. Evaluate a solution to a complex real-world problem based on prioritized criteria and trade-offs that account for a range of constraints, including cost, safety, reliability, and aesthetics as well as possible social, cultural, and environmental impacts.

Academic Content Lesson 1 – Zip Line Basics – the fundamental physics concepts in zip lines Activity 1 – Zip and Deliver – an introduction to engineering design through an activity on zip line design Activity 2 – Zoom Zoom – investigating the forces experienced on zip lines

Academic Content Lesson 2 – Zip Line Design Project –zip line trolley system design Activity 3 – Zip Stop – designing a rating system for zip line braking mechanisms Activity 4 – Zip Ride – designing a safe zip line trolley system with a braking mechanism

Zip Line Design Project Engineering Design

Vector Resolution in Physics Addition of Vectors (1+2+3) Vector magnitude angle x-component y-component Vector 1 20.0000 30.0000 17.3205 10.0000 Vector 2 60.0000 15.0000 25.9808 Vector 3 40.0000 120.0000 -20.0000 34.6410 Resultant 71.6884 80.1039 12.3205 70.6218

MatLab Code Automates this process Graphs the individual vectors Graphs the individual vectors as if they were graphed individually (head to tail method) as well as the resultant vector

MatLab Graphs

MatLab Command Window Results

Resources 1. http://adventure.howstuffworks.com/zip-line1.htm 2. http://www.ziplinerider.com 3. http://www.acctinfo.org/