一、填空题 1.光线以人射角艺从空气射向折射率n二涯的透明媒质表面(如图4一1),若人射角i=450,则反射光线与折射光线间的夹角O= 当人射角i=图4一1时,反射光线与折射光线间的夹角0=900.(105。,arctg夜) 2.用共扼法测定凸透镜焦距的实验中 (l)甲同学实验时,先将光源和屏的位置固 First, fill in the blank 1. Light rays to the human angle of art from the air to the refractive index n two horizon transparent media surface (Figure 4-1), if the angle of incidence i = 450, the reflected light and refraction of light between the folder Angle O = angle between reflected light and refracted light 0 = 900 when ray angle i = Fig. 4-1. (105., arctg night) 2. In the experiment of determining the focal length of the convex lens by the conjugation method (1) A classmate experiment, the first light source and screen position solid