(a) A simple compound microscope is built of two convex lenses with focal lengths 1 em (objective) and 4em (eyepiece). (1) Draw a ray diagram to demonstrate how the microscope works in far-point adjustment. Label the positions of the object and the lenses as well as the focal lengths of the lenses. Show the position of the virtual image that the observer sees. (11) The two lenses are now moved closer to each other and the eyepiece becomes the ohjective (and vice versa) so that they act as a telescope. Calculate the magnifving power of the system. (11) Explain what is meant by chromatic aberration and its effect on an image observed though a system of lenses. Objective lens fe fo Parallel rays Eye lens from object at infinity Fo Fe a C B' B. Eye A Final image at infinityRay diagram of the image formed at infinity by refracting telescope is shown here which indicates that focal length of objective lens and that of eye piece is f, and f. respectively. Magnifying power of telescope is defined as the ratio of angle subtended by image on eye (p) to angle subtended by object on eye (a) Magnifying power of telescope m = b From figure, p = tan 3 = AfB Also,a = tana = E 0 P_ 1o a f. = m=t f, e