Chapter 13.2, Problem 12R

To determine

Maximum distance between the lens and the object.

Explanation of Solution

Introduction:

A convex lens is thicker at the inside and thinner at the outer ends of the lens. It is called converging lens.

Focal length of the convex lens is given: $f=15\text{ cm}$

Now, the image formed will be real, inverted and enlarged only if the object is placed between the two focal lengths: $\text{F and 2F}$

So, the maximum distance between the lens and the object is given as:

  $2\text{F}=2\times 15\text{cm}=30\text{ cm}$

Conclusion:

Hence, the maximum distance between the lens and the object is $30\text{ cm}$ .