Laser Maze
Discovery Lab Investigation
NGSS:
MS-ETS1-4.
Develop a model to generate data for iterative testing and modification of a proposed
object, tool, or process such that an optimal design can be achieved.
MS-PS4-2.
Develop and use a model to describe that waves are reflected, absorbed, or
transmitted through various materials.[Clarification Statement: Emphasis is on both light
and mechanical waves. Examples of models could include drawings, simulations, and
written descriptions.] [Assessment Boundary: Assessment is limited to qualitative
applications pertaining to light and mechanical waves.]
Outcomes:
 Participants can describe that light travels in waves called transverse waves.
 Participants can describe what transverse waves may do when they encounter
materials, as well as identify and create examples of each interaction.
o Reflect, absorb, transmit (refraction), scattering/diffusion
Lab Overview
In a quick introduction, our scientist uses a tank of colored fluid and a laser to demonstrate
what light waves can do when they encounter matter. Students observe reflection, transmission
(refraction), and absorption, and work with our scientist to label each action with the appropriate term.
Then students are challenged to use a bin of materials to create an interesting maze/path for a
laser to take, which includes at least two instances of reflection, transmission, and absorption. We
provide mirrors, a green (532 nm wavelength) laser, a black/white target, and several transparent
blocks in a variety of shapes. To make the challenge a bit more intriguing, students must place their
target directly behind their laser! Once groups have their maze constructed, they are challenged to
label each instance of wave-material interaction with the proper term. If time allows, groups may get
the opportunity to view the work of other groups.
This lab helps your students use technical terms and gain hands-on experience with a
foundational set of wave principles. They are also challenged to playfully use an engineering design
cycle as they design and redesign their laser maze creation to meet our criteria. Students are
encouraged to get creative and innovative as they design and build their laser maze so they may be
up and moving, using materials in unexpected ways, and safely pushing the limits of this lab.
Key Concepts: wave, reflection, transmission,
absorption, scattering/diffusion
 Transverse Wave – Light travels as a transverse wave.
Waves that move the material they are in at right angles to
the direction in which the waves energy travels are called
transverse waves. Transverse means "across". So as a
transverse wave moves to the right, the particles of the
medium move up and down at right angles to the direction
of the wave.
 Reflection – When a transverse wave hits a material it may
bounce off of the surface. A surface may absorb some
wavelengths and reflect others; the reflected wavelengths allow us
to see colors. Simple or specular reflection happens when light hits a
smooth surface, then the angle of reflection is always equal to the
angle of incidence.
o Diffusion – When light hits a rough surface the light
reflects in many different directions all at once and the
light appears to spread out. A good example of diffusion is the way a bright car
headlight or street light seems to spread out in fog.
 Transmission – A transverse wave may pass through a
transparent or translucent material. There are several types of
transmission, but the most common is refraction.
o Refraction refers to the bending of light that occurs
when it travels through transparent media that have
different refractive indices. The reason that it bends is
connected to the fact that light travels at different
speeds in different media.
 Absorption – Light can be soaked up or absorbed by a
material. Absorbed light will not reflect or transmit through a material. Absorbed light is often
transformed into heat energy. White light hitting an object may be partially absorbed and partially
reflected; those wavelengths of light that reflect give the object the color we see. Black objects
appear black because nearly all wavelengths are
absorbed. White objects look white because nearly all
wavelengths have been reflected back to our eyes.