Looking Through a Copper Pipe (Stephen H)

Author

Stephen

Principle(s) Illustrated

• Wave properties of light

• Diffraction of light

• Constructive and destructive interference.

Standards

• HS-PS4-3. Evaluate the claims, evidence, and reasoning behind the idea that electromagnetic radiation can be described either by a wave model or a particle model, and that for some situations one model is more useful than the other.

• PS4.A: Wave Properties

• Waves can add or cancel one another as they cross, depending on their relative phase (i.e., relative position of peaks and troughs of the waves), but they emerge unaffected by each other. (Boundary: The discussion at this grade level is qualitative only; it can be based on the fact that two different sounds can pass a location in different directions without getting mixed up.)

• PS4.B: Electromagnetic Radiation

• Electromagnetic radiation (e.g., radio, microwaves, light) can be modeled as a wave of changing electric and magnetic fields or as particles called photons. The wave model is useful for explaining many features of electromagnetic radiation, and the particle model explains other features.

• CCC

• 1. Patterns. Observed patterns of forms and events guide organization and classification, and they prompt questions about relationships and the factors that influence them.

Questioning Script

Prior knowledge & experience:

Students are use to seeing light reflect of surfaces.

Root question:

What will it look like when you look down a copper pipe?

Target response:

Concentric circles. Pattern of light and dark.

Common Misconceptions:

Students are unfamiliar with the concept of constructive and destructive interference.

Photographs and Movies

Copper Pipe (unexpected interesting pattern)

Galvanized Pipe (expected)

References

Grating Phyiscs - Newport