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...
Against this background, the problem of change in the intensity of the earth's magnetic field and its possible reversal has been discussed little so far, although the authors of this article consider the consequences of these processes destructive for the humanity. A high probability of ...
C.the magnetic strength of the Earth will disappearD.the magnetic strength of the Earth will be stronger 相关知识点: 试题来源: 解析 B 第三段第四句开始:磁场的转换给人类和动物带来许多问题。宇航员和卫星会遇到很多困难,依靠磁场指示方向迁徙的鸟类、鱼类和其他动物会在迁徙中失去方向。
A. the compass will become useless B. man and animals will be confused as to directions C. the magnetic strength of the Earth will disappear D. the magnetic strength of the E. arth will be stronger 相关知识点: 试题来源: 解析 B 正确答案:B 解析:第三段第四句开始:磁场的转换给人类和动物...
A. the compass will B. ecome useless. B man and animals will be confused as to directions. C. the magnetic strength of the Earth will D. isappear. D the magnetic strength of the E. arth will be stronger. 相关知识点: 试题来源: 解析 B 反馈 收藏 ...
The Earth's magnetic field is generated mainly by _. A. the movement of the outer core B. the rotation of the crust C. the presence of water on the surface D. the heat from the sun 相关知识点: 试题来源: 解析 A。解析:地球的磁场主要是由外地核中液态金属的流动产生的。地壳的旋转与...
A. there would be no change on Earth B. the atmosphere would be gradually stripped away C. the Earth would stop rotating D. all living things would die immediately 相关知识点: 试题来源: 解析 B。解析:如果地球磁场突然消失,大气层会逐渐被剥离。地球磁场消失会对地球产生巨大影响,A选项错误。地球...
Changes in the Earth's magnetic field over the past century: Effects on the ionosphere-thermosphere system and solar quiet (Sq) magnetic variation [1]We investigated the contribution of changes in the Earth's magnetic field to long-term trends in the ionosphere, thermosphere, and solar quiet (...
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...
doi:10.1038/161160a0SYDNEY CHAPMAN F.R.SNature