My mother’s parents came from Hungary, but my grandfather could trace his origin to Germany and also he was educated in Germany. Although he was able to hold a conversation in nine languages, he was most comfortable in German. Every morning, before going to his office, he read tile ...
解析 B 正确答案:B解析:本题考查考生的理解能力,根据原文内容“During a reversal,the main field weakens, almost vanish-es,and reappears with opposite polarity.”在反向运转时,主要的磁场就会减弱,几乎彻底消失,甚至重新出现相反的磁极。根据这句话可以知道,地球磁场开始向它的反方向改变,所以B比较符合题意。
Parameters of the Earth's magnetic field observed near the surface of the planet vary in space and time over wide ranges. As well as processes acting in the deep interior of Earth, the crust, the ionosphere, the magnetosphere, and the Sun all contribute to the observed magnetic field. ...
As the field originates in the Earth's molten core, the palaeomagnetic record is crucial to the understanding of both the origin and evolution of the geomagnetic field and the Earth's deep interior. 展开 关键词: geomagnetism geomagnetic observations spatial and temporal variations magnetic activity...
Preface The observation of the Earth's magnetic field is destined to play a crucial role in understanding the Earth system. The great potential of ground magnetic observations allows an impressive coverage of a diverse range of topics in the modern "magnetic world", in particular (i) development...
A. begun to change in the opposite direction B. been weakening in strength for a long time C. caused the changes on the polarities D. misguided many a man and animal 相关知识点: 试题来源: 解析 B 正确答案:B 解析:文章第一段:《纽约时报》上周报道地球磁场严重减弱开始于150年前。磁场保护...
This is because the magnetic field(磁场) of the Earth "protects" us from the "wind".At the North and South Poles, however, some particles may get in and meet with the Earth's air. Then, the particles get "excited" and have a "dance" with the air. So, we can see the moving ...
(a) The earth is surrounded by a magnetic field generated by the magnetism in the core of the earth. Small magnetic grains in rocks will orient themselves to be parallel to the direction of the magnetic field pointing towards the north pole. (b) The geomagnetic polarity time scale shows ...
(redirected fromEarth's magnetic field) Encyclopedia Wikipedia ge·o·mag·ne·tism (jē′ō-măg′nĭ-tĭz′əm) n. 1.The magnetism of the earth. 2.The study of the earth's magnetism. ge′o·mag·net′ic(-nĕt′ĭk)adj. ...
This approach makes it possible to automatically extract different kinds of disturbances in the Earth's magnetic field variations, which characterize solar activity and help to predict magnetic storms. In order to analyze geomagnetic signals wavelet packets are used in order to isolate local variations...