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.

Answer 1

(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

Answer 2

i dn't no the answer for case b pls help me