一、知识脉络1.光的传播①光源是指正在发光的物体。②光的直线传播条件是在同种均匀介质中如常见现象:月食、日食、影子等;应用于光准直、现象解释等;光线是表示光的传播方向和路径的带箭头的直线。③光的本质是一种电磁波;真空中光速c=3×10~8m/s;介质中小于c。2.光的反射①常见现象。②光的反射定律:反射光线与入射光线、法线三线共面;反射光线与入射光线分居法线 First, the light 1. The spread of light ① light is the object is glowing. ② light linear propagation conditions in the same homogeneous medium such as common phenomena: eclipses, solar eclipse, shadow, etc .; used in light collimation, the phenomenon of interpretation; light is the direction of light and path of the arrow with a straight line . ③ the essence of light is an electromagnetic wave; vacuum speed c = 3 × 10 ~ 8m / s; medium is less than c. 2 light reflection ① common phenomenon. ② law of reflection of light: reflected light and incident light, the normal three-line coplanar; reflected light and incident light separation normal