A telescope has an objective lens with a focal length of 90 cm and an eyepiece of focal length 3.0 cm. What is the angular magnification of the telescope?
Which of the following would decrease the magnification of a compound microscope?
A) Replacing the objective lens with one of larger diameter.
B) Replacing the eyepiece lens with one of shorter focal length.
C) Replacing the eyepiece lens with one of smaller diameter.
D) Replacing the objective lens with one of longer focal length.
Even relatively small astronomical telescopes are ordinarily not used for terrestrial observation because:
A) their images are not in color.
B) their images are inverted.
C) their images are too bright.
D) their images are too dim.
A refracting astronomical telescope has objective and eyepiece lenses of focal lengths 38 cm and 0.40 cm, respectively. What is the angular magnification of this instrument?