Kinetic and Potential Energy of Motion

In this lesson, students are introduced to both potential energy and kinetic energy as forms of mechanical energy. A hands-on activity demonstrates how potential energy can change into kinetic energy by swinging a pendulum, illustrating the concept of conservation of energy. Students calculate the potential energy of the pendulum and predict how fast it will travel knowing that the potential energy will convert into kinetic energy. They verify their predictions by measuring the speed of the pendulum. This engineering curriculum meets Next Generation Science Standards (NGSS).

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Standards & Objectives

Learning objectives:

After this lesson, students should be able to:

Recognize that engineers need to understand the many different forms of energy in order to design useful products
Explain the concepts of kinetic and potential energy.
Understand that energy can change from one form into another.
Understand that energy can be described by equations.

Essential and guiding questions:

Pre-Introduction:

What are examples of dangerous unsafe placement of objects? (Possible answers: Boulders on the edge of a cliff, dishes barely on shelves, etc.).

Post-Introduction:

What has more potential energy: a boulder on the ground or a feather 10 feet in the air? (Answer: The feather because the boulder is on the ground and has zero potential energy. However, if the boulder was 1 mm off the ground, it would probably have more potential energy.)

Lesson Variations

Blooms taxonomy level:

Applying

Extension suggestions:

There is another form of potential energy, not related to height, which is called spring potential or elastic potential energy. In this case, energy is stored when you compress or elongate a spring. Have the students search the Internet or library for the equation of spring potential energy and explain what the variables in the equation represent.

Interdisciplinary opportunities:

Engineering Connection:
Mechanical engineers are concerned about the mechanics of energy — how it is generated, stored and moved. Product design engineers apply the principles of potential and kinetic energy when they design consumer products. For example, a pencil sharpener employs mechanical energy and electrical energy. When designing a roller coaster, mechanical and civil engineers ensure that there is sufficient potential energy (which is converted to kinetic energy) to move the cars through the entire roller coaster ride.

References

Contributors:

Lindsay Talarico

Originator:

Ayers Institute for Learning & Innovation