Because when an object is in motion it has kinetic energy
Answer:
2.27 cm
2.5 cm
Explanation:
u = Object distance = 25 cm
v = Image distance = 2.5 cm
f = Focal length
Lens Equation

The minimum effective focal length of the focusing mechanism of the typical eye is 2.27 cm
when 

The maximum effective focal length of the focusing mechanism of the typical eye is 2.5 cm