Measure the Width of Human Hair

How do STEM professionals measure at nanoscale? With a laser, of course!

In this STEM lab, learn how to use a laser for measuring the tiniest things – like the width of a human hair! This hands on lesson brings STEM to light! Students will determine width of human hair using diffraction and a laser of known wavelength.

Grade Range: 9 to 14

Duration: 1/2 Hour – 1 Hour


  • Red and green Laser Blox
  • Tape
  • Meter stick
  • Blank wall
  • Hair

NGSS Connections

PS4.B – Electromagnetic Radiation

  • Use mathematical representations to support a claim regarding the relationships between the frequency, wavelength and speed of waves traveling in various media.

Science and Engineering Practices

  • Use mathematical representations of phenomena or design solutions to describe and/or support claims and/or explanations
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Includes NGSS Standards and Student Worksheets

Get safe laser pointers designed for this lesson

Our Laser Blox are designed for educational use at home and in the classroom. We test every batch to ensure total power is within safe limits and the magnetic housing keeps the laser pointing the right direction when used on a steel surface.

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