一、填空题 1.由太阳发出的光大约经8分20秒才能到达地球,所以太阳与地球之间的距离大约是_米. 2.经过光的反射总能成缩小、正立虚像的镜子是 镜;经过光的折射能够成放大、正立虚像的镜子是镜. 3.一凸透镜焦距为f,要在透镜的另一侧得到一个缩小的实像,则物距u_;若要使物像在透 First, fill in the blanks 1. The light from the sun reaches Earth about 8 minutes and 20 seconds, so the distance between the Sun and the Earth is about _ meters. 2. The mirror that reflects the light can always be reduced and erected. Mirror; The mirror through the light refraction can be enlarged, erect virtual image is a mirror. 3. A focal length of the convex lens is f, to get a reduced real image on the other side of the lens, the object distance u_; To make the object image in through