【简答题】( 2018 苏州市) 14.人类通过对微观世界的探索,认识到原子是由带负电的电子和带正电的 ▲ 组成 .在橡胶棒与毛皮摩擦过程中,毛皮_ ▲ 电子 ,使橡胶棒带负电。 ( 2018辽宁营口) 15.15.当玻璃棒和丝绸摩擦时,丝绸带______电,是因为在摩擦过程中丝绸______ 选填 “得到”或“失去” 电子。反复摩擦后,发现玻璃棒的温度升高,这是通过 ______方式改变物体内能的。
【单选题】橡胶棒与毛皮摩擦后,毛皮带正电荷,这是因为摩擦使毛皮 ( )
【单选题】用毛皮摩擦过的橡胶棒吸引轻小纸屑后,纸屑又很快飞开,这是因为( )
C.
纸屑与橡胶棒接触后带正电荷,同种电荷相互排斥,所以飞开。
D.
纸屑与橡胶棒接触后带负电荷,同种电荷相互排斥,所以分开。
【单选题】毛皮与橡胶棒摩擦后,毛皮带正电,这是因为( )。
【单选题】高校开展防盗知识宣传,主要对象是( )。
【单选题】大气中海市蜃楼现象的出现是由于大气光的()
【单选题】毛皮与橡胶棒摩擦后,毛皮带正电,这是因为
【单选题】Directions: Read the " Formula One History ",After reading the passage, you will find 8 unfinished statements or questions. For each question or statement, please choose the best answer from the four ...
【单选题】Year after year a dedicated Swedish chemist worked to find a substance which, when (1)_____ nitroglycerine(硝化甘油), would make explosives safer to handle (2)_____ weakening their force. He had a persona...
【简答题】Chapter 4, Problem 49 The chemical formula for an intermetallics compound of Cu and Al is Cu 2 Al. According to the formula, the atom percent of Al should be exactly 33.33% (one out of three atoms sh...