What’s on the Refraction poster
The rule, 3 worked examples, and the mistake everyone makes.
- The ratio of the sines of the angles equals the inverse ratio of the speeds.
- n₁ sin θ₁ = n₂ sin θ₂ · n = c/v
- Into a denser medium = Bends toward the normal
- Into a less dense medium = Bends away from the normal
- Along the normal = No bending
- Common mistake: Saying the wave slows because it bends → It bends because it slows
Refractive index n = c/v, always greater than 1 in a material. Frequency never changes at a boundary.
Questions about the Refraction poster
- What’s on the Refraction poster?
- The rule, 3 worked examples, and the mistake everyone makes. The ratio of the sines of the angles equals the inverse ratio of the speeds.; n₁ sin θ₁ = n₂ sin θ₂ · n = c/v; Into a denser medium = Bends toward the normal; Into a less dense medium = Bends away from the normal; Along the normal = No bending; Common mistake: Saying the wave slows because it bends → It bends because it slows. Refractive index n = c/v, always greater than 1 in a material. Frequency never changes at a boundary.
- Who is the Refraction poster for?
- Refraction belongs to the Physics section rather than to a school year, because physical science is not something one grade owns. Anyone learning waves & optics can pin it up — a beginner, a student mid-course, or someone revising years later.
- When should you use the Refraction poster?
- Speed changes at the boundary. The change in direction follows from it. A wall chart earns its place by being glanceable from where the work is happening, so Refraction belongs on the wall where that physical science work actually happens, within glancing distance, rather than filed away.
- What other posters go with Refraction?
- Diffraction Gratings, The Doppler Effect and Lenses sit alongside Refraction in the Physics section. Printed together they make a wall rather than a single sheet, which is how a reference set actually gets used.Diffraction GratingsThe Doppler EffectLenses
- Is the Refraction poster free to download and print?
- Yes. Refraction downloads as a free PDF with no account, no email and no watermark, like everything else in the Physics section. Print as many copies as you like for a home, a classroom, a library or a tutoring group; reselling the file is the only thing the licence rules out.Read the licence
- What size does the Refraction poster print at?
- Refraction is a vector PDF laid out for US Letter, and prints on A4 with Fit to page — the same file, no separate download. Because every mark on it is drawn rather than photographed, it stays sharp enlarged to A3, A2 or A1 at a copy shop. Colour carries emphasis only, so a greyscale print of Refraction loses nothing.Printing guide
Related posters
Charts that sit alongside Refraction on the same wall.
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