Suppose that image of the Sun is focussed on a screen using a thin lens whose focal length is 27 cm. We have to find the diameter of the image.
|
Solution: Click For PDF Version We will use the result that the magnitude of the lateral magnification of the size of an object and its image formed by a thin lens is given by the relation
where
From the astronomical data we note that
mean distance
of the Earth from Sun,
and the solar
equatorial radius,
As the image
of the Sun is formed using a thin lens of focal length
Therefore,
the diameter of the Sun’s image as seen on a screen using a
thin lens of focal length
|
,
is the object distance and
is the image distance.
,
.
,
the image distance
