Question

If a convex lens (converging) has a focal length of 12 cm, where would you place an object in order to produce an image that has the same height, but inverted?Less than 12 cm6 cm12 cm24 cm

Answer 1

Given that the focal length is F = 12 cm.

We need to find the position of the object such that the image obtained should be inverted, the same height as that of the object.

In a convex lens, for the image to be inverted and the same height as the object, it should be placed at 2F.

So, the object position will be

$\begin{gathered} 2F=2\times12 \\ =24\text{ cm} \end{gathered}$

Thus, the object position should be 24 cm.