CBSE notes-Light

 CBSE notes-Light

What is the nature, size and position of the image formed of an object at infinity? Explain how it is used as a doctor’s mirror.

When an object is placed at infinity from a concave mirror, the image formed is
(i) real and inverted
(ii) highly diminished and
(iii) at the focus
When the object is at infinity, the image is formed at the focus of the concave mirror, hence the mirror can concentrate all the parallel rays of the light to its focus. This explains the use of concave mirror as a doctor’s head-mirror. A concave mirror is used as a head-mirror by the doctors to concentrate light on the body parts to be examined.

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