posted by william .
A 4.5 cm long insect is perpendicular to the optical axis of a thin lens; the bug is 5.4 cm away from the lens. The lens forms an inverted image of the insect which is 0.9 cm long on a screen behind the lens.
a. How far behind the lens is the screen?
b. What is the lens' focal length (pay attention to sign)?
c. If the insect were instead only 0.25 cm from the lens, what would the image distance be (pay attention to sign)?
d. Could the new image be projected on a screen?