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Mistake Master · AP Physics 2 · Unit 13 · Step-Through Animation

Light Bends When It Changes Speed

You'll learnwhy light bends when it enters glass or water, which way it bends, and when it cannot get out at all.

A beam of light crosses from air into glass and bends. Send it back out too steeply and it cannot leave at all. Twelve short steps; press Next for each one.

12 STEPS · 6 QUICK CHECKS · WHICH WAY IT BENDS · TRAPPED LIGHT · THE PRISM · v2

slower bends toward the normal · too steep and it cannot get out
Before you start
What you're looking at
A beam of light meeting the surface of a glass block. The dashed line is the normal, the reference line at right angles to the surface.
The question
Which way does light bend when it crosses, and can it ever get stuck?
Step 1 / 12