How can You Demonstrate the Efficiency of Different Light Bulbs?

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In this activity, learners actually feel the difference in energy required to light two different types of light bulbs: incandescent light and LEDs. Learners will use a generator (hand crank) to provide the power and observe that the bulbs are equally bright. They will be surprised to learn that incandescent bulbs require more energy. This is a hands-on activity that works best if learners experience cranking the generator themselves, and works well at a learning station or center. This activity can be incorporated into a lesson on energy efficiency and/or used during winter holidays since it uses holiday lights.

Quick Guide

Preparation Time:
Under 5 minutes

Learning Time:
5 to 10 minutes

Estimated Materials Cost:
$5 - $10 per group of students

Age Range:
Ages 8 - 14

Resource Types:
Activity, Lesson/Lesson Plan


Materials List (per group of students)

  • 1 hand generator
  • 2 alligator clip leads, 1 black and 1 red
  • 1 cluster of 6 white LED Christmas tree lights
  • 1 cluster of 6 clear incandescent Christmas tree lights
  • Infrared goggles (optional)


  • Engineering and Technology
    • Technology
  • Physical Sciences
    • Electricity and Magnetism
    • Energy
    • Vibration and Waves
      • Light and Optics
    • Light and Optics
      • Electromagnetic Spectrum
  • The Nature of Science
    • The Scientific Process
      • Conducting Investigations
      • Formulating Explanations
  • The Nature of Technology
    • Technology and Society


To use this activity, learners need to:

  • see
  • touch

Learning styles supported:

  • Involves hands-on or lab activities


Components that are part of this resource:

This resource is part of:

Access Rights:

  • Free access



  • All rights reserved, Little Shop of Physics, 2009

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