posted by Agu .
An object is placed (a)6cm (b)20 from a thin convex lens of focal length 10cm.determine the nature,position and magnification of the image in each case.
(a) and (b) are separate problems, not multiple choices.
For the first case, letting di be the image distance from the lens, use the standard lens equation
1/6 + 1/di = 1/f = 1/10
1/di = 6/60 - 10/60 = -4/60 = -1/15
di = -15 cm
The image is "virtual" upright and magnified by a ratio |15/6| = 2.5
Now you do case b
i dn't no the answer for case b pls help me