Telescope Quiz

The two most important properties of any telescope are

• the light-gathering power and the length of the tube.

• the length of the tube and the magnification.

• the magnification and the light-gathering power.

• the resolving power and the magnification.

• the light-gathering power and the resolving power.

A pencil inside a water glass appears to be bent because of

• reflection of light.

• refraction of light.

• diffraction of light.

• None of these choices are correct.

Tags

NGSS.MS-PS4-2

What is a disadvantage of using a single large lens in a telescope?

• Large lenses are expensive to fabricate.

• A lens has to be supported only at its edges, so the lens can sag in the middle.

• Different colors of white light on passing through a lens focus at different points and result in a blurred image.

• Some lens materials completely absorb short wavelengths.

• All of these choices are correct.

How does the light-gathering power of a telescope affect the ability to see faint objects?

• Faint objects are brighter if the telescope can gather a lot of light.

• Faint objects appear larger when viewed through a large-diameter telescope.

• Faint objects do not twinkle if the telescope can gather a lot of light.

• Faint objects are clearer (better resolved) if the telescope can gather a lot of light.

What is the difference between a reflecting and a refracting telescope?

• A reflecting telescope uses a lens to focus light; a refracting telescope uses a mirror.

• A reflecting telescope uses a mirror to focus light; a refracting telescope uses a lens.

• Both use a mirror to focus light, but a reflecting telescope uses mirrors elsewhere to bend light.

• There is no difference. "Refracting" is an outmoded way of saying "reflecting."

Tags

NGSS.MS-PS4-2

Astronomy’s largest optical telescopes are ____.

• reflectors

• refractors

• diffractors

• deflectors

Chromatic aberration creates images fringed with color when using which kind of telescope?

• reflector

• refractor

• radio

• interferometer

• adaptive optic

Tags

NGSS.HS-PS4-5

When light passes through a transparent material, different wavelengths (colors) of light are refracted by differing amounts. This effect is called ____.

• reflection

• diffraction

• dispersion

• aberration

• scintillation

Which of these is a reason for using mirrors rather than lenses in telescopes?

• Lenses are more expensive to make than mirrors.

• Most transparent materials focus light of different colors to different spots.

• Lenses can only be supported by their edges, making them sag in the middle (mirrors can be supported from behind).

• All of these choices are correct.

In a reflecting telescope, the secondary mirror causes a hole in the center of the image.

• True

• False