Light Trapped in an Acrylic Rod

Light stays inside and exits at far end. Ask students to predict what will happen. Shine light into one end and bend/angle rod. Key idea: At suitable angles, light repeatedly reflects inside instead of escaping. Ask: Why doesn't light leak out at every surface? Safety and cleanup: LED only; no lasers. https://www.google.com/search?q=%22Light+Trapped+in+an+Acrylic+Rod%22+science+demonstration+experiment