Chapter 23, Problem 33Q

To determine

(a)Can’t measure the focal length of the diverging lens

(b)The converging lens must be stronger the diverging lens

Answer to Problem 33Q

Solution:

(a)The final image is formed at infinity by the second lens.

(b)Converging lens does not have a shorter focal length than the diverging lens

Explanation of Solution

(a)When an object is placed so that its image from one converging lens is placed at the focal point of a second converging lens, the final image is formed at infinity by the second lens.

(b)A real image is similar to a real object and when this image is placed at the focal point of another lens, the rays will head to the second lens in such a way as to be sent out on the other side of the lens in a direction parallel to the optical axis, which forms an image at infinity. the converging lens does not have a shorter focal length than the diverging lens, then the converging lens’ image (which will be a virtual object for the diverging lens)will be too far away from the diverging lens and it will just form another virtual image.