当光从空气斜射入水或玻璃等透明物质中时,折射角______入射角;当光从水或玻璃 发布时间:2017-05-22 06:25 │ 来源:www.tikuol.com 题型:填空题 问题: 当光从空气斜射入水或玻璃等透明物质中时,折射角______入射角;当光从水或玻璃等透明物质斜射入空气中时,折射角______入射角.(口诀“空大透小”)
题型:填空题 测定饮用水的耗氧量时,水样采集和保存,我国《生活饮用水标准检验法》中所采用的方法为()A.用玻璃瓶取样,于冰箱保存7日内测定B.用玻璃瓶取样,于室温保存7日内测定C.用玻璃瓶取样,每升水样加0.8mlHCl,4℃保存,24小时内测定D.用玻璃瓶取样,每升水样加0.8mlHNO3 ,4℃保存,24小时内测定E.用玻璃瓶取样,每升水样加0.8mlH2 SO4 ,4℃保存,24小时内测定 查看答案
题型:填空题 Swimming is my favorite sport. There is _____ like swimming as a means of keeping fit. [ ]A. something B. anything C. nothing D. everything 查看答案