反射与折射
Reflection & Refraction
阐述反射定律（入射角等于反射角），并解释折射是光在穿过两种介质的界面时速度和方向发生的变化；会画平面镜和折射面的光线图。
State the law of reflection (angle of incidence = angle of reflection) and explain refraction as the change in speed and direction when light crosses a boundary between two media; apply ray diagrams for plane mirrors and refracting surfaces
学习证据 / Evidence
- 说出反射定律，并运用它正确画出反射光线。
- 画出平面镜的光路图，显示虚像。
- 用折射解释为什么铅笔在玻璃杯的水中看起来是弯折的。
- 能定性解释为什么光进入更密的介质时会向法线方向偏折。
- States the law of reflection and applies it to draw a reflected ray correctly
- Draws a ray diagram for a plane mirror showing a virtual image
- Explains why a pencil looks bent in a glass of water using refraction
- Explains qualitatively why light bends towards the normal when entering a denser medium
评估问题 / Assessment
如果{{name}}把一根吸管放进一杯水里，看到吸管在水面处看起来弯折了，{{name}}能解释这是为什么吗——并画一张图来显示光在水面上的路径？
If {{name}} put a straw in a glass of water and it looked bent at the surface, could they explain why that happens — drawing a diagram to show the path of light at the water’s surface?