Question

For the telescope is in normal adjustment (i.e., when the final image is at infinity)? what is the separation between the objective lens and the eyepiece?

Answer 1

Focal length of the objective lens, f_o = 140 cm

Focal length of the eyepiece, f_e = 5 cm

In normal adjustment, the separation between the objective lens and the eyepiece = f_o + f_e = 140  + 5 = 145 cm