The size of the image of an object, which is at infinity, as formed by a convex lens of focal length 30 cm is 2 cm. If a concave lens of focal length 20 cm is placed between the convex lens and the image at a distance of 26 cm from the convex lens, calculate the new size of the image |
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a) |
1.25 cm |
b) |
2.5 cm |
c) |
1.05 cm |
d) |
2 cm |
The size of the image of an object, which is at infinity, as formed by a convex lens of focal length 30 cm is 2 cm. If a concave lens of focal length 20 cm is placed between the convex lens and the image at a distance of 26 cm from the convex lens, calculate the new size of the image |
|||||||
a) |
1.25 cm |
b) |
2.5 cm |
c) |
1.05 cm |
d) |
2 cm |
(b)
Image formed by convex lens at will act as a virtual object for concave lens. For concave lens
Or cm
Magnification for concave lens
As size of the image at is 2 cm. Therefore, size of image at will be cm.