Energy and the Pogo Stick
Two people guide the pogo stick and one takes measurements.Copyright 2005 Joel Daniel, Vanderbilt University
Students learn about the conservation of energy with the inclusion of elastic potential energy. They use pogo sticks to experience the elastic potential energy and its conversion to gravitational potential energy.
Not only do engineers need to know about elastics energy, but also how to measure it. This lab, like the previous rollercoaster activity, has students measuring data and then calculating energy from that raw data. Engineers use these concepts in designing and testing pogo sticks as well as many other objects designed to move.
After this activity, students should be able to:
- Apply their background knowledge to begin solving the challenge.
- Relate elastic potential energy with gravitational potential energy.
- Hypothesize about experimental "error."
- CCSS.Math.Content.HSA-CED.A.4 Rearrange formulas to highlight a quantity of interest, using the same reasoning as in solving equations.
Grades 9-12
Do you agree with this alignment? - CCSS.Math.Content.HSA-REI.B.3 Solve linear equations and inequalities in one variable, including equations with coefficients represented by letters.
Grades 9-12
Do you agree with this alignment?
- Use computers and calculators to access, retrieve, organize, process, maintain, interpret, and evaluate data and information in order to communicate.
Grades 9-12
Do you agree with this alignment? - Energy cannot be created nor destroyed; however, it can be converted from one form to another.
Grades 9-12
Do you agree with this alignment? - STEL-8N Use various approaches to communicate processes and procedures for using, maintaining, and assessing technological products and systems.
Grades 9-12
Do you agree with this alignment?
- Physical Science
Grades K-12
Do you agree with this alignment? - Science and Technology
Grades K-12
Do you agree with this alignment?
- HS-PS3-1 Create a computational model to calculate the change in the energy of one component in a system when the change in energy of the other component(s) and energy flows in and out of the system are known.
Grades 9-12
This resource focuses on the following Three Dimensional Learning aspects of NGSS:
Science & Engineering Practices- Create a computational model or simulation of a phenomenon, designed device, process, or system.Do you agree with this alignment?
Disciplinary Core Ideas- Energy is a quantitative property of a system that depends on the motion and interactions of matter and radiation within that system. That there is a single quantity called energy is due to the fact that a system's total energy is conserved, even as, within the system, energy is continually transferred from one object to another and between its various possible forms.Do you agree with this alignment?
- Conservation of energy means that the total change of energy in any system is always equal to the total energy transferred into or out of the system.Do you agree with this alignment?
- Energy cannot be created or destroyed, but it can be transported from one place to another and transferred between systems.Do you agree with this alignment?
- Mathematical expressions, which quantify how the stored energy in a system depends on its configuration (e.g. relative positions of charged particles, compression of a spring) and how kinetic energy depends on mass and speed, allow the concept of conservation of energy to be used to predict and describe system behavior.Do you agree with this alignment?
- The availability of energy limits what can occur in any system.Do you agree with this alignment?
Crosscutting Concepts- Science assumes the universe is a vast single system in which basic laws are consistent.Do you agree with this alignment?
- Models can be used to predict the behavior of a system, but these predictions have limited precision and reliability due to the assumptions and approximations inherent in models.Do you agree with this alignment?
Do you agree with this alignment? - Create a computational model or simulation of a phenomenon, designed device, process, or system.
- HS-PS3-2 Develop and use models to illustrate that energy at the macroscopic scale can be accounted for as either motions of particles or energy stored in fields.
Grades 9-12
This resource focuses on the following Three Dimensional Learning aspects of NGSS:
Science & Engineering Practices- Develop and use a model based on evidence to illustrate the relationships between systems or between components of a system.Do you agree with this alignment?
Disciplinary Core Ideas- Energy is a quantitative property of a system that depends on the motion and interactions of matter and radiation within that system. That there is a single quantity called energy is due to the fact that a system's total energy is conserved, even as, within the system, energy is continually transferred from one object to another and between its various possible forms.Do you agree with this alignment?
- At the macroscopic scale, energy manifests itself in multiple ways, such as in motion, sound, light, and thermal energy.Do you agree with this alignment?
- These relationships are better understood at the microscopic scale, at which all of the different manifestations of energy can be modeled as a combination of energy associated with the motion of particles and energy associated with the configuration (relative position of the particles). In some cases the relative position energy can be thought of as stored in fields (which mediate interactions between particles). This last concept includes radiation, a phenomenon in which energy stored in fields moves across space.Do you agree with this alignment?
Crosscutting Concepts- Energy cannot be created or destroyed—it only moves between one place and another place, between objects and/or fields, or between systems.Do you agree with this alignment?
Do you agree with this alignment? - Develop and use a model based on evidence to illustrate the relationships between systems or between components of a system.
- CCSS.Math.Content.HSA-CED.A.4 Rearrange formulas to highlight a quantity of interest, using the same reasoning as in solving equations.
Grades 9-12
Do you agree with this alignment? - M1.A.REI.A.1 Solve linear equations and inequalities in one variable, including equations with coefficients represented by letters.
Grades 9-12
Do you agree with this alignment?
- 3204.2.1 Differentiate among the various forms of energy.
Grades 9-12
Do you agree with this alignment? - CLE 3202.2.6 Investigate the Law of Conservation of Energy.
Grades 9-12
Do you agree with this alignment?
Each group needs:
- pogo stick
- book
- ruler
- Energy Pogo Stick Worksheet, one per student
Students must have a basic working knowledge of dry lab operations and measurements. They should also have an understanding of elastic and potential energies as well as be able to calculate spring constants.
In today's activity, we will apply what we have learned about the conservation of energy between elastic and gravitational potential energies to a hands-on activity. As you learn about elastic potential energy, be thinking about how you could use the transformation of energy to design your hybrid car. Be especially thinking about how you might use elastic potential energy in your car design.
Background
This activity introduces students to the concept of conservation of energy, solely between elastic and gravitational potential energy. Refer back to the associated lesson, Elastic Potential Energy of Springs—It’s Tiggerific!, for more information on the conversion of kinetic and gravitational potential energy to elastic potential energy.
Before the Activity
Gather materials and make copies of the Energy Pogo Stick Worksheet, one per student.
With the Students
Explain the Lab Procedure:
- Divide the class into lab groups of 4-5 students each. Have each take and record his/her own mass.
- Record the distance from the ground to the collar of the pogo stick.
- Calculate the spring constant by using the mass of the person on the pogo stick and the deflection of the pogo stick.
- Have two people on each side of the person on the pogo stick bouncing him/her up and down. Have one or two people on the ground directly in front of the other group, measuring the amount of deflection of the collar of the pogo with a ruler that is taped to the spine of a book.
- On the last bounce, the spotters on each side of the person on the pogo should release, but still guide the person vertically. The measurer(s) should measure both the distance of deflection and the height that the collar actually achieves.
- Use these distances to calculate the amount of elastic potential energy and the amount of gravitational potential energy.
The teacher then needs to explain how to make height measurements of the pogo stick, as the bouncers are allowing the pogo stick to bounce freely. The teacher should also point out any potential hazards that may result in decreased safety and/or increased error. These include issues as not letting the person on the pogo actually jump, but to have the spotters actually bounce him/her up and down, making sure that the pogo is bounced straight up and down, and only taking the measurements on the last bounce as the pogo is allowed to bounce freely.
Assess students by their contributions during the lab, as well as the completeness and accuracy of their lab reports.
- For lower grades, provide more time for group discussions and have only the teacher be on the pogo stick.
- For upper grades, have students hypothesize possible types of energy that might be associated with a percentage of less than 1 in (refer to the first Investigating Question).
Contributors
Joel Daniel (Center for Compact and Efficient Fluid Power, University of Minnesota); Megan Johnston
Supporting Program
VU Bioengineering RET Program, School of Engineering, Vanderbilt University
Acknowledgements
The contents of this digital library curriculum were developed under National Science Foundation RET grant nos. 0338092 and 0742871. However, these contents do not necessarily represent the policies of the NSF, and you should not assume endorsement by the federal government.
Copyright
2013 by Regents of the University of Colorado; original © 2006 Vanderbilt University