26.5 Telescopes

Which of the following is an advantage to using a concave mirror in the construction of a telescope?

1. The telescope can gather more light than a telescope using lenses.
2. The telescope does not suffer from chromatic aberration.
3. The telescope can provide greater magnification than a telescope using lenses.

1. I and III only
2. II only
3. I and II only
4. I, II, and III

Two concave lenses, of focal lengths 500 mm and 20 mm, are used in the construction of a telescope. Given any potential arrangement, what is the largest possible magnification the telescope may have?

1. 100×
2. 10,000×
3. 25×
4. 4×

Unless otherwise stated, the lens-to-retina distance is 2.00 cm.

What is the angular magnification of a telescope that has a 100 cm focal length objective and a 2.50 cm focal length eyepiece?

Unless otherwise stated, the lens-to-retina distance is 2.00 cm.

A large reflecting telescope has an objective mirror with a $\text{10} . 0 m$ radius of curvature. What angular magnification does it produce when a 3.00 cm focal length eyepiece is used?

Unless otherwise stated, the lens-to-retina distance is 2.00 cm.

A $7.5×$ binocular produces an angular magnification of $- 7 . \text{50}$, acting like a telescope. (Mirrors are used to make the image upright.) If the binoculars have objective lenses with a 75.0 cm focal length, what is the focal length of the eyepiece lenses?