Ray diagrams are used to find the position and size of an image, and to determine whether the image is real or virtual. The light from the object travels out in all direction, but we can pick any rays we want to find the image. Most ray diagrams, like the ones in the following examples, pick the same two light rays to determine the location and size of the image.

Click through the following images to view the steps to find an image with a plane mirror:

Take out a blank piece of paper and draw a ray diagram to determine the smallest possible mirror that you would need to see an image of your entire body.

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Check Your Answer

The following diagram illustrates that the minimum length of a plane mirror required for someone to view their entire image equals half their height. Note that the top of the mirror should be placed at eye level.