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Question
A man sits in an optician's chair looking into plane mirror which is 2 m away from him and views the image of a chart which faces the mirror and is 50 cm behind his head. How far away from his eyes does the chart appear to be?
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Solution
he image of the chart will appear 4.5 m away from the eye.
The image of the chart will form at a distance of 2 m + 0.5m = 2.5 m behind the mirror. The reason being, the image formed by a plane mirror is at the same distance behind it as it is between the object and the mirror.
Thus,
distance of the chart's image from the eye = distance of man from the mirror + distance of image formed behind the mirror = 2 + 2.5 = 4m.
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