An optician while testing the eyes of a patient keeps a chart of letters 3 m behind the patient and asks him to see the letters on the image of chart formed in a plane mirror kept at distance 2 m in front of him. At what distance is the chart seen by the patient ?
An optician while testing the eyes of a patient keeps a chart of letters 3 m behind the patient and asks him to see the letters on the image of chart formed in a plane mirror kept at distance 2 m in front of him. At what distance is the chart seen by the patient ?
The chart of letters is at a distance of 3 m behind the patient.
The mirror is kept at distance of 2 m in front of patient
Hence
The distance of chart from the mirror is
2+3=5 m
Now
we know that a plane mirror forms an image at a distance equal to the object distance but inside the mirror.
Hence
The image of the chart is formed 5 m inside the mirror.
Therefore the distance of image of chart from patient is
→Distancetotheplanemirror+distancebetweenchartandplanemirror=2+5=7m
→∴d=2+5=7m
Answer :- 7 m
The chart of letters is at a distance of 3 m behind the patient.
The mirror is kept at distance of 2 m in front of patient
Hence
The distance of chart from the mirror is
2+3=5 m
Now
we know that a plane mirror forms an image at a distance equal to the object distance but inside the mirror.
Hence
The image of the chart is formed 5 m inside the mirror.
Therefore the distance of image of chart from patient is
→Distancetotheplanemirror+distancebetweenchartandplanemirror=2+5=7m
→∴d=2+5=7m
Answer :- 7 m
