An object is placed in front of convex surface of a glass
piano-convex lens of thickness d = 9.0 cm. The image of that object
is formed on the plane surface of the lens serving as'a screen. Find:
(a) the transverse magnification if the curvature radius of the
lens's convex surface is R = 2.5 cm;
(b) the image illuminance if the luminance of the object is L
7700 cdim2 and the entrance aperture diameter of the lens is
D = 5.0 mm; losses of light are negligible.