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?

In a barber's shop, two plane mirrors are placed:

1. perpendicular to each other
2. parallel to each other
3. at an angle of 60° between them
4. at an angle of 45° between them.

The number of images formed for two mirrors kept perpendicular to each other is :

1. 1
2. 2
3. 3
4. 5

A thick plane mirror, silvered at its back, forms multiple number of images. Out of these, the brightest image is :

1. first image
2. second image
3. third image
4. All are of equal brightness