1. If a boy is standing 2.5m in front of a plane mirror, then at what distance is the image of the boy (a) from the mirror (b) from the boy himself? If the boy walks towards the mirror with a speed of 0.5 m/s, at what distance will the image of the boy be from himself after 1s (one second)
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Answers
Explanation:
A plane mirror makes an image of objects in front of it; these images appear to be behind the plane in which the mirror lies. A straight line drawn from part of an object to the corresponding part of its image makes a right angle with, and is bisected by, the surface of the plane mirror. The image formed by a plane mirror is always virtual (meaning that the light rays do not actually come from the image), upright, and of the same shape and size as the object it is reflecting. A virtual image is a copy of an object formed at the location from which the light rays appear to come. However, the image is a laterally-inverted "mirror image” of the object.
If a boy is is moving towards a plane mirror, the image of his right hand appears to be the left hand of the image.Suppose, the velocity of the observer is ‘v’ towards the mirror. In the mirror, the image velocity is’(-v)’.The image velocity w.r.t boy is;
v=2.5 m/s
-v=-2.5 m/s
Velocity of image w.r.t boy = velocity of object - velocity of image
velocity w.r.t to boy = v - (-v)
=2.5 - (-2.5)
The image velocity is 5 m/s towards the boy