A 5.00 cm tall candle is placed at a distance of 50.0 cm from a double convex lens having a focal length of 15.0 cm. What is the magnification of the image?

Question

-0.429

-2.33

0.429

2.33

Answer 1

(1/p) + (1/q) = 1/f
M = h'/h = -q/p,

Where p is distance of object from lens, q is distance of image from lens, f is focal length of the lens, and M is the magnification

f is positive when the lens is convex:

1/50 + 1/q = 1/15

q = 21.4 cm
M = -21.4/50