Question

A 2.63 cm high insect is 1.25 m from a 120 mm focal-length lens. Where is the image?How high is the image?
cm What type is it?

Answer 1

From the given data

i) Distance of object (insect) from the lens is

ii) height of object (insect) is

iii) Focal length of lens is

a) Distance of image from the lens is given by

substitute the known values,

  

Thus, the image is at a distance of from lens

b) Height of Image:

Magnification factor is given by

Substitute the known values,

  

here negative value of image represents its an inverted image.

Consider magnification factor.

  

Since magnification factor is less than 1, the image is diminished image