问题
应用设计题
利用身边现在器材：电子秤、一次性茶杯和足量的水．设计一个测定小石块密度的实验方案．要求写出简要的实验步骤和小石块密度的表达式．
答案
实验步骤：
①用电子秤测出空茶杯质量m1
②将茶杯装满水，测出总质量m2
③倒掉水，在烧杯中放入适量小石块测出总质量m3，再往茶杯中注满水测出总质量m4；
④计算石块密度
表达式：
ρ石=
ρ水
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利用身边现在器材：电子秤、一次性茶杯和足量的水．设计一个测定小石块密度的实验方案．要求写出简要的实验步骤和小石块密度的表达式．
实验步骤：
①用电子秤测出空茶杯质量m1
②将茶杯装满水，测出总质量m2
③倒掉水，在烧杯中放入适量小石块测出总质量m3，再往茶杯中注满水测出总质量m4；
④计算石块密度
表达式：
ρ石=ρ水
阅读下面短文，将短文下面方框里A—E五个句子填入文中空缺处，使内容完整正确 Mr Johnson worked in a restaurant. He worked there for ten years. 76 .And at last he was sent away. He hated hard work and stayed in the city. Once something was wrong with his ear. He had to see a doctor. 77 .And five minutes later he had to pay the doctor twenty dollars. He thought it was easy to get much money. So he came to the small town and opened a hospital. 78 .But soon they found he couldn’t treat them at all and his medicine wasn’t useful. People hardly came and he had nothing to do. One evening he heard a knock at the door. 79 .He thought he had a bad cold and he asked him to take some medicine . After that the man left. 80 . On the third day a young man came in and said, “ Thank you very much, doctor!” It surprised Mr Johnson. He said, “I haven’t seen you before. What do you thank me for?” “My uncle died from your wrong treatment the day before yesterday and he left much money to me.”
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