如图,滑轮重小于物重(绳重、摩擦不计〉。使用甲图滑轮最大的好处是 ;若匀速提 发布时间:2017-07-21 09:24 │ 来源:www.tikuol.com 题型:填空题 问题: 如图,滑轮重小于物重(绳重、摩擦不计〉。使用甲图滑轮最大的好处是 ;若匀速提升相同的重物,则F甲 F乙、机械效率ŋ甲 ŋ乙(“<”/“=”/“>”)。
题型:填空题 Part A You will hear a lecture about shingles, an infectious disease. As you listen, answer Questions 1 to 10 by circling TRUE or FALSE. You will hear the talk ONLY ONCE. You now have 1 minute to read Question 1 to 10.Questions 1 to 10:Complications of shingles can only affect the body part like heart, lungs, liver, and pancreas but not nerves in brain. 查看答案
题型:填空题 一列横波沿x轴正方向传播,其波速为v=5.0m/s,t=0时刻的波刚好传播到A点,此时波形如图所示,下列说法中正确的是( )A.质点A振动周期为2sB.在t=0.1s时,质点A处于波谷C.在t=2.5s时,x=4m的质点B的速度最大D.在t=2.5s时,x=5m的质点C位于波谷 查看答案