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HOW WE USE LIGHT 



Does this convex mirror give a real or an 

 unreal image ? 



unreal image because there is no light that really goes to 

 the place where we appear to see the image. When a real 

 image is formed, as in a camera, rays of light actually form 



the image where the 

 image is seen. 



Curved Mirrors. 

 You have probably 

 seen a crystal globe. 

 This is a spherical 

 mirror. A small por- 

 tion of the spherical 

 surface would also be 

 called a spherical mirror. It is also a convex mirror. 

 Sometimes a convex mirror is placed on the fender or 

 on an arm projecting to the left of the wind shield of a 

 truck or automobile. The curved surface makes a larger 

 area visible, and an image is seen just as in a plane 

 mirror except that it is smaller. Perhaps you have 

 looked into the convex cylindrical mirrors at some 

 amusement park and have seen yourself tall and thin 

 or short and fat. 



The inside of a 

 spherical surface is 

 concave. A con- 

 cave mirror will 

 focus rays of light 

 from a distant ob- 

 ject and make a 

 real and enlarged 

 image. Large 

 mirrors of this type 

 are used in the re- 



How to look stout or thin. Why do some mirrors 

 change your appearance ? 



fleeting telescopes for viewing the stars. Enlarging 

 mirrors are useful and can readily be obtained. The 

 dentist uses a small enlarging mirror to see your teeth 



