| D. | changes its speed to the speed of sound in glass. |
| 2. | What is the refraction of light?A. | the readjust in direction of a light ray together it reflects from a much more dense product than the one in which that is traveling |
| B. | the absorb of light as it traverses a dense, transparent material |
| C. | the breaking of white light into its composite colors |
| D. | the adjust in direction the a light ray as it crosses from a much less dense, transparent material to a much more dense one |
| 3. | Which characteristic of a glass lens is the most crucial in bending light rays to form a concentrated image?A. | curvature and also shape the its surfaces |
| C. | diameter or size of the lens |
| D. | thickness of the center of the lens |
| 4. | The key optical facet in a refracting telescope is aA. | lens. |
| C. | combination that many small plane mirrors. |
| 5. | Who was the very first astronomer to build and use a telescope to observe the night sky?A. | Copernicus |
| 6. | The significant reason astronomers look for funds to develop larger telescopes is toA. | bring stars closer to Earth. |
| B. | measure a wider spectrum of light from stars. |
| C. | provide magnified images the stars. |
| D. | collect more light from remote objects. |
| 7. | For many years, the Palomar telescope (5 m diameter) in California was the largest completely steerable telescope in the world; currently that honor falls to among the 2 Keck telescopes (each that diameter 10 m) in Hawaii. How plenty of times larger is the light-gathering strength of the Keck telescope 보다 the Palomar telescope?A. | 2 time larger |
| 8. | In a correctly focused refracting telescope, the objective lens and the eyepiece lens space separated through a distance equal come the (see Fig. 6-5, Freedman and also Kaufmann, Universe, 6th ed.)A. | focal length of the eyepiece. |
| B. | focal length of the objective minus the focal length of the eyepiece. |
| C. | sum that the focal length lengths that objective and eyepiece. |
| D. | focal length of the objective. |
| 9. | Which the the following varieties of telescope will endure from chromatic aberration unless really expensive steps are taken to avoid it?A. | radio telescope |
| 10. | Chromatic aberration occurs in a refracting telescope whenA. | some wavelengths are reflected from the front surface of the target lens of the telescope. |
| B. | light from some wavelengths is took in by the lenses, thereby developing false colour of objects. |
| C. | the lenses bending under their very own weight, in order to distorting the final image. |
| D. | all colour of light execute not come to the very same focal point. |
| 11. | If you desire to build a telescope having actually the least possible amount that chromatic aberration, you need to useA. | mirrors instead of lenses. |
| B. | as thin a prior lens together possible. |
| C. | a prior lens that has actually been coated v a special material to minimize refraction. |
| D. | a front lens that is composed of two carefully spaced lenses make of various kinds of glass. |
| 12. | When a beam of light strikes a smooth mirror surface ar at an edge to the perpendicular, the beam is reflectedA. | at various angles, depending upon wavelength. |
| B. | back along its initial (incoming) path. |
| C. | so the it travels follow me the perpendicular to the surface ar of the mirror. |
| D. | on the "other" side of the perpendicular yet at the same angle as the just arrived ray. |
| 13. | How is a Newtonian showing telescope constructed?A. | A collection of winter channel the light to a far location. |
| B. | It has actually a concave primary mirror and flat, diagonal second mirror. |
| C. | A concave primary mirror, through a concave an additional mirror that reflects light back through a hole in the main mirror. |
| D. | A concave primary mirror, v a convex secondary mirror that shows light ago through a feet in the primary mirror. |
| 14. | When light from the concave main mirror the a telescope is reflect by a small an additional mirror v a hole in the primary, the is calledA. | prime focus. |
| 15. | If part of the main mirror that a mirroring telescope is clogged off by a little screen, i beg your pardon of the following features of the final image is affected?A. | Although the brightness is unaffected, the size of the image will it is in reduced. |
| B. | A part of the image is missing. |
| C. | Only the brightness is reduced. |
| D. | Depending top top which part of the winter is obscured, the color of the image is affected. |
| 16. | To produce the sharpest images of an extremely distant objects, the finest shape for the cross-section the a large astronomical mirror have to beA. | elliptical. |
| C. | perfectly flat and also smooth. |
| 17. | A spherical mirror suffers from spherical aberration becauseA. | the starlight is distorted by turbulence in the Earth"s atmosphere. |
| B. | the winter sags under its very own weight, distorting the image. |
| C. | different parts of the mirror emphasis the irradiate at various distances indigenous the mirror. |
| D. | different colour are concentrated at different distances native the mirror. |
| 18. | The major mirror in the 10-m Keck telescope is do fromA. | one large, slim slab that glass whose surface is continuously changed by computer-controlled motors. |
| B. | 36 separation, personal, instance mirrors, placed so the they all carry the irradiate to the very same focus. |
| C. | six individual mirrors placed so that they all carry the light to the same focus. |
| D. | one huge slab the glass made very thick to protect against sagging. |
| 19. | In telescopes, the resolution is worse forA. | larger diameter lenses or winter and shorter wavelength light (or other electromagnetic radiation). |
| B. | smaller diameter lenses or mirrors and longer wavelength irradiate (or various other electromagnetic radiation). |
| C. | smaller diameter lenses or winter and much shorter wavelength light (or various other electromagnetic radiation). |
| D. | larger diameter lenses or mirrors and longer wavelength irradiate (or various other electromagnetic radiation). |
| 20. | At the too much limit that magnification, the significant cause of blurred and also unsharp images of objects observed v very huge telescopes isA. | the poor tracking ability of contemporary telescopes. |
| B. | air turbulence in the Earth"s atmosphere. |
| C. | the poor optical polishing achievable on large mirrors. |
| D. | the clumsiness of the telescope operator. |
| 21. | It is difficult to boost the angular resolution the optical telescopes located on the surface ar of the Earth beyond a specific limit becauseA. | we would require to build larger telescopes and also this is an extremely expensive. |
| B. | spherical mirrors suffer from too much aberration. |
| C. | air disturbance distorts the star images an ext than walk the telescope optics. |
| D. | large telescopes are constantly reflecting telescopes and these endure from too much chromatic aberration. |
| 22. | What aspect has seriously decreased the effectiveness of the telescopes approximately the world, such together those in ~ Mt. Palomar in California and at Kitt Peak, near Tucson, Arizona, end the last few years?A. | tarnishing that the mirror surface by air pollution |
| B. | cracking that the mirror by earthquakes |
| C. | bending that the mirror surface ar from repeated exposure come the cold night air |
| D. | light scattering in the atmosphere from nearby cities |
| 23. | The detector the in plenty of instances has replaced the photographic plate for huge photography is theA. | diffraction grating. |
| B. | CCD (charge-coupled device). |
| D. | PMT (photomultiplier tube). |
| 24. | The charged-coupled an equipment (CCD), currently used extensively for expensive imaging, works on what principle?A. | Light generates electric charge ~ above a computer-readable, multi-element variety of detectors. |
| B. | Light from the photo modifies the plastic product on a disk, which can then be read on a standard video compact decaying (CD) player. |
| C. | Light indigenous the photo is detected by new, high-sensitivity, fine-grain, automatically processed film. |
| D. | A single optical detector generates an electric signal together it is scanned quickly across the astronomical image. |
| 25. | A spectrograph is usually provided in astronomy to measure theA. | variation the the mass of things as it moves through space. |
| B. | distribution of irradiate intensity among the miscellaneous colors. |
| C. | vibration of earth following an earthquake. |
| D. | brightness of irradiate at one particular color. |
| 26. | How walk angular resolution because that a offered diameter that telescope depend on wavelength?A. | Angular resolution intensifies as wavelength increases. |
| B. | Angular resolution improves as wavelength increases. |
| C. | Angular resolution may enhance or worsen together wavelength increases, relying on other components such together intensity and spectral selection (e.g., optical, infrared, radio). |
| D. | Angular resolution depends just on the diameter of the telescope and also is live independence of wavelength. |
| 27. | The angular resolution attainable v a radio telescope, contrasted to that attainable v an optical telescope of the very same diameter, is considerably inferior becauseA. | the wavelength that radio tide is bigger than that of visible light. |
| B. | it is complicated to make a reflector because that radio waves due to the fact that these waves penetrate most materials. |
| C. | the Earth"s atmosphere disturbs radio waves from room much much more than that does visible light. |
| D. | radio wavelength are smaller than visible wavelengths, do it an overwhelming to develop a reflector sufficiently smooth to develop images. |
| 28. | What is the main reason because that combining numerous radio telescopes together into an interferometer with large distances in between telescopes?A. | to obtain much sharper photos of sources |
| B. | to ensure that at the very least one that the telescopes is in a radio interference-free zone |
| C. | to for sure that monitorings are uninterrupted through the failure of one or 2 telescopes |
| D. | to collect an ext radiation from really faint sources |
| 29. | The two varieties of electromagnetic radiation for which Earth"s atmosphere is reasonably transparent areA. | UV and also radio waves. |
| B. | visible and also far infrared radiation. |
| C. | X rays and also visible radiation. |
| D. | visible and also radio radiation. |
| 30. | Astronomy from space vehicles is particularly useful since the telescopeA. | is in a clean, dust-free environment and scattered irradiate is lot reduced. |
| B. | is over Earth"s soaking up and distortion atmosphere and can measure radiation over a very wide wavelength range. |
| C. | is in a gravity-free state, its winter is no distorted through gravitational stress, and it can develop sharper images. |
| D. | moves clear in a constant orbit and can produce sharp photographs. |
| 31. | For which of the complying with spectral ranges is it important that huge observations it is in made native space?A. | visible |
| 32. | After the Hubble an are Telescope to be launched, that was found to experience seriously fromA. | chromatic aberration. |
| C. | too much angular resolution. |
| D. | jittery photos caused by strong stratospheric winds. |
| 33. | The very first nonvisible radiation detected from outer space wasA. | X rays. |
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