A lab specimen is 15.2 mm from a converging lens. The image is 4.0 mm tall and 9.0 cm from the lens. How tall is the specimen?
A) 1.7 mm
B) 5.4 mm
C) 0.68 mm
D) 6.8 mm

Question

Quizplus · Accepted Answer

Using the lens formula and magnification formula, the magnification (m) is given by the ratio of image distance (v) to object distance (u), m = v/u. Here, v = 9.0 cm = 90 mm, u = 15.2 mm. So, m = 90/15.2. The height of the specimen (h) is given by the height of the image (h') divided by magnification, h = h'/m. Given h' = 4.0 mm, h = 4.0 / (90/15.2) = 0.68 mm.

A Lab Specimen Is 15