Passage Reading and English Comprehension

Virtually everything astronomers know about objects outside the solar system is based on the detection of photons—quanta of electromagnetic radiation. Yet there is another form of radiation that permeates the universe: neutrinos. With (as its name implies) no electric charge, and negligible mass, the neutrino interacts with other particles so rarely that a neutrino can cross the entire universe, even traversing substantial aggregations of matter, without being absorbed or even deflected. Neutrinos can thus escape from regions of space where light and other kinds of electromagnetic radiation are blocked by matter. Furthermore, neutrinos carry with them information about the site and circumstances of their production: therefore, the detection of cosmic neutrinos could provide new information about a wide variety of cosmic phenomena and about the history of the universe.

But how can scientists detect a particle that interacts so infrequently with other matter? Twenty-five years passed between Pauli’s hypothesis that the neutrino existed and its actual detection: since then virtually all research with neutrinos has been with neutrinos created artificially in large particle accelerators and studied under neutrino microscopes. But a neutrino telescope, capable of detecting cosmic neutrinos, is difficult to construct. No apparatus can detect neutrinos unless it is extremely massive, because great mass is synonymous with huge numbers of nucleons (neutrons and protons), and the more massive the detector, the greater the probability of one of its nucleon’s reacting with a neutrino. In addition, the apparatus must be sufficiently shielded from the interfering effects of other particles.

Fortunately, a group of astrophysicists has proposed a means of detecting cosmic neutrinos by harnessing the mass of the ocean. Named DUMAND, for Deep Underwater Muon and Neutrino Detector, the project calls for placing an array of light sensors at a depth of five kilometers under the ocean surface. The detecting medium is the seawater itself: when a neutrino interacts with a particle in an atom of seawater, the result is a cascade of electrically charged particles and a flash of light that can be detected by the sensors. The five kilometers of seawater above the sensors will shield them from the interfering effects of other high-energy particles raining down through the atmosphere.

The strongest motivation for the DUMAND project is that it will exploit an important source of information about the universe. The extension of astronomy from visible light to radio waves to x-rays and gamma rays never failed to lead to the discovery of unusual objects such as radio galaxies, quasars, and pulsars. Each of these discoveries came as a surprise. Neutrino astronomy will doubtless bring its own share of surprises.

280. Which of the following titles best summarizes the passage as a whole?

	(a) At the Threshold of Neutrino Astronomy
	(b) Neutrinos and the History of the Universe
	(c) The Creation and Study of Neutrinos
	(d) The DUMAND System and How It Works

281. With which of the following statements regarding neutrino astronomy would the author be most likely to agree?

	(a) Neutrino astronomy will supersede all present forms of astronomy.
	(b) Neutrino astronomy will be abandoned if the DUMAND project fails.
	(c) Neutrino astronomy can be expected to lead to major breakthroughs in astronomy.
	(d) Neutrino astronomy will disclose phenomena that will be more surprising than past discoveries.

282. In the last paragraph, the author describes the development of astronomy in order to

	(a) suggest that the potential findings of neutrino astronomy can be seen as part of a series of astronomical successes
	(b) illustrate the role of surprise in scientific discovery
	(c) demonstrate the effectiveness of the DUMAND apparatus in detecting neutrinos
	(d) name some cosmic phenomena that neutrino astronomy will illuminate

283. According to the passage, one advantage that neutrinos have for studies in astronomy is that they

	(a) have been detected for the last twenty-five years
	(b) possess a variable electric charge
	(c) are usually extremely massive
	(d) carry information about their history with them

284. According to the passage, the primary use of the apparatus mentioned would be to

	(a) increase the mass of a neutrino
	(b) interpret the information neutrinos carry with them
	(c) detect the presence of cosmic neutrinos
	(d) see neutrinos in distant regions of space

285. The passage states that interactions between neutrinos and other matter are

	(a) rare
	(b) artificial
	(c) undetectable
	(d) unpredictable

286. The passage mentions which of the following as a reason that neutrinos are hard to detect?

	(a) Their pervasiveness in the universe
	(b) Their ability to escape from different regions of space
	(c) The infrequency of their interaction with other matter
	(d) The similarity of their structure to that of nucleons

287. According to the passage, the interaction of a neutrino with other matter can produce

	(a) particles that are neutral and massive
	(b) a form of radiation that permeates the universe
	(c) inaccurate information about the site and circumstances of the neutrino’s production
	(d) charged particles and light

288. According to the passage, one of the methods used to establish the properties of neutrinos was

	(a) detection of photons
	(b) observation of the interaction of neutrinos with gamma rays
	(c) observation of neutrinos that were artificially created
	(d) measurement of neutrinos that interacted with particles of seawater

TOTAL

Detailed Solution

1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20
21	22	23	24	25	26	27	28	29	30	31	32	33	34	35	36	37	38	39	40
41	42	43	44	45	46	47	48	49	50	51	52	53	54	55	56	57	58	59	60
61	62	63	64	65	66	67	68	69	70	71	72	73	74	75	76	77	78	79	80
81	82	83	84	85	86	87	88	89	90	91	92	93	94	95	96	97	98	99	100
101	102	103	104	105	106	107	108	109	110	111	112	113	114	115	116	117	118	119	120
121	122	123	124	125	126	127	128	129	130	131	132	133	134	135	136	137	138	139	140
141	142	143	144	145	146	147	148	149	150	151	152	153	154	155	156	157	158	159	160
161	162	163	164	165	166	167	168	169	170	171	172	173	174	175	176	177	178	179	180
181	182	183	184	185	186	187	188	189	190	191	192	193	194	195	196	197	198	199	200
201	202	203	204	205	206	207	208	209	210	211	212	213	214	215	216	217	218	219	220
221	222	223	224	225	226	227	228	229	230	231	232	233	234	235	236	237	238	239	240
241	242	243	244	245	246	247	248	249	250	251	252	253	254	255	256	257	258	259	260
261	262	263	264	265	266	267	268	269	270	271	272	273	274	275	276	277	278	279	280
281	282	283	284	285	286	287	288	289	290	291	292	293	294	295	296	297	298	299	300
301	302	303	304	305	306	307	308	309	310	311	312	313	314	315	316	317	318	319	320
321	322	323	324	325	326	327	328	329	330	331	332	333	334	335	336	337	338	339	340
341	342	343	344	345	346	347	348	349	350	351	352	353	354	355	356	357	358	359	360
361	362	363	364	365	366	367	368	369	370	371	372	373	374	375	376	377	378	379	380
381	382	383	384	385	386	387	388	389	390	391	392	393	394	395	396	397	398	399	400
401	402	403	404	405	406	407	408	409	410	411	412	413	414	415	416	417	418	419	420
421	422	423	424	425	426	427	428	429	430	431	432	433	434	435	436	437	438	439	440
441	442	443	444	445	446	447	448	449	450	451	452	453	454	455	456	457	458	459	460
461	462	463	464	465	466	467	468	469	470	471	472	473	474	475	476	477	478	479	480
481	482	483	484	485	486	487	488	489	490	491	492	433	494	495	496	497	498	499	500

Passage Reading Verbal Logic Non Verbal Logic Numerical Logic Data Interpretation Reasoning Analytical Ability Basic Numeracy About Us Contact Privacy Policy Major Tests FAQ

---