Learning how to fly took nature millions of years of trial and errorbut a winged robot has cracked it in only a few hours, using the same evolutionary principles. To begin with, the robot just twitched and jerked erratically. But, gradually, it made movements that gained height. At first , it cheated simply standing on its wing tips was one early short cut. After three hours, however, the robot abandoned such methods in favor of a more effective flapping technique, where it rotated its wings through 90 degrees and raised them before twisting them back to the horizontal and pushing down. The robot had metre-long wings made from balsa wood and covered with a light plastic film. Small motors on the robot let it move its wings forwards or backwards, up or down or twist them in either direction. A computer program fed the robot random instructions, at the rate of 20 per second, to test its flapping abilities. Each instruction told the robot either to do nothing or to move the wings slightly in the various directions. 1.Which of the following is NOT true of what is mentioned about the winged robot in the second paragraph? B. The two professors of CUT tested whether the winged robot could learn to fly. D. The two professors of CUT tried to find out if the robot could fly by itself. A. It rotated its wings through 90 degrees. C. It was twitched and broke down. 3.Which of the following is nearest to Peter Bentleys view on the winged robot? B. The winged robot did not have a mortor. D. The robot could fly if it were lighter. A. Two vertical rods. B. A movement detector. 5.What does the process appearing in the last paragraph refer to? B. Sending instructions to the robot. D. All the above.
外研版[2013版]英语八上Unit2《It descibes the changes in Chinese society》ppt课件1
初二外研上册module4 Unit 3
外研版[2013版]英语八上Unit2《The WWF is working hard to save them all》ppt课件包(含音频)
外研英语初二英语上学期module3Unit 3
外研版[2013版]英语八上Unit2《This year we practise more carefully》ppt课件
八年级英语上学期Uint2 Section A 新目标
外研英语初二英语上学期module4Unit 2
外研英语初二英语上学期module3 revision
外研版初二英语(上)Module 11 Unit 1 对话
八年级英语上学期Translations
八年级英语上学期Module 2 Unit 1外研英语
外研初二上Module5 Unit 3
外研英语初二上学期8A Module 3 Unit 2
八年级英语上学期module1(Unit 1)外研英语
外研版[2013版]英语八上Unit2《It descibes the changes in Chinese society》ppt课件2
外研版八年级上Module11 Unit 3 Language in use
外研英语初二英语上学期module2
外研版[2013版]英语八上Unit2《It descibes the changes in Chinese society》ppt课件3
八年级英语上学期the past participle tense外研英语
外研版[2013版]英语八上Unit2《It describes the changes in Chinese society》ppt课件包(含音频)
八年级英语上学期反意疑问句 外研英语
外研初二上 Module4 Unit 3
外研英语初二上学期module1 unit 1
外研英语初二英语上学期module 2
八年级英语上学期module 7 unit 3外研英语
外研英语初二英语上学期module4Unit 1
外研版[2013版]英语八上Unit2《The WWF is working hard to save them all》ppt课件1
外研英语初二(上)Module 5 unit 2
八年级英语上学期Revision Module 1外研英语
外研版8年级上册Module3 Unit 1 Has it arrived yet
不限 |
英语教案 |
英语课件 |
英语试题 |
不限 |
不限 |
上册 |
下册 |
不限 |