【判断题】结构的地震反应是一种动力反应,其大小(如振动幅值)不仅与地面运动有关,还与结构动力特性(自振周期、振型和阻尼)有关。
【单选题】选择幼儿园教学活动内容的要求包括:了解幼儿、 、抓住疑问、 。
【简答题】A. classification B. compare and contrastC. process ysisD. cause and effect E. problem and solution4. In recent decades, cities have grown so large that now about 50% of the Earth's pop...
【简答题】A. classification B. compare and contrastC. process ysisD. cause and effect E. problem and solution5. The Loggerhead sea turtle is threatened. Conservationists are attempting to help th...
【简答题】相位用于表示周期性运动中每一个周期内各状态。对简谐振动,相位为0,下面哪种说法是正确的?
【简答题】A. classification B. compare and contrastC. process ysisD. cause and effect E. problem and solution3. To pick the best restaurant for that romantic night out, a number of questions must...
【简答题】A. classification B. compare and contrastC. process ysisD. cause and effect E. problem and solution2. There are as many kinds of restaurants as there are occasions to eat out, but the t...
【单选题】( 多选 ) (2018· 山西省长治、运城、大同、朔州、阳泉五地市联考 ) 下列说法正确的是 ( ) A. 日光灯是紫外线的荧光效应的应用 B. 单摆在做受迫振动时,它的周期等于单摆的固有周期 C. 机械波从一种介质进入另一种介质后,它的频率保持不变 D. 麦克斯韦第一次用实验证实了电磁波的存在 E. 弹簧振子做简谐振动时,振动系统的势能与动能之和保持不变