新人教版二年级数学上册《认识时间》课件.ppt

15 25 53 45 56=,口算练习题,5,55 51 55 52 54,10,15,20,30,25,5,10,10,20,75 25 59 85 57=,口算练习题,35,45 65 55 52 54,10,45,40,35,20,30,25,10,20,我有一个好朋友， 嘀哒嘀哒不停走， 叫我学习和休息， 真是我的好朋友！,猜谜语,钟表,认识时间,分针长长指12, 时针指几就几时。,9时,1时,7时,时间王国,钟面上都有什么？,D,K,X,S,F,M,大格,刻度,小格,时针,分针,秒针,1,2,3,4,5,7,6,8,11,12,10,9,1,2,3,4,5,7,6,8,11,12,10,9,分针走 1小格是1分。走几个小格就是几分。,1,2,3,4,5,7,6,8,11,12,10,9,5,一个大格有5个小格。,我知道了：分针从12起，走到1是5分， 走到2是10分，走到3是,1,2,3,4,5,7,6,8,11,12,10,9,( ),( ),5,10,15,1,2,3,4,5,7,6,8,11,12,10,9,5,1,2,3,4,5,7,6,8,11,12,10,9,5,10,1,2,3,4,5,7,6,8,11,12,10,9,5,10,15,1,2,3,4,5,7,6,8,11,12,10,9,5,10,15,20,1,2,3,4,5,7,6,8,11,12,10,9,5,10,15,20,25,1,2,3,4,5,7,6,8,11,12,10,9,5,10,15,20,25,30,1,2,3,4,5,7,6,8,11,12,10,9,5,10,15,20,25,30,35,1,2,3,4,5,7,6,8,11,12,10,9,5,10,15,20,25,30,35,40,1,2,3,4,5,7,6,8,11,12,10,9,5,10,15,20,25,30,35,40,45,1,2,3,4,5,7,6,8,11,12,10,9,5,10,15,20,25,30,35,40,45,50,1,2,3,4,5,7,6,8,11,12,10,9,5,10,15,20,25,30,35,40,45,50,55,1,2,3,4,5,7,6,8,11,12,10,9,5,10,15,20,25,30,35,40,45,50,55,60,钟面上一共60个小格。,1,2,3,4,5,7,6,8,11,12,10,9,5,10,25,30,20,15,60,35,40,45,50,55,12时30分,30分也可以说是半小时,12时,12时30分,1时,30分也可以说是半小时,拨时游戏,12,1,2,3,4,5,6,7,8,9,10,11,演示,时针走一大格 分针走一圈,时,=,60分,一分钟有多长,在一分钟的时间内,能做些什么？,1分大约跑200米。,1分大约骑700米。,1分大约游50 米。,一分钟，铅笔厂可生产铅笔1600支。 一分钟，银行点钞机可以数1500张人民币。 一分钟，核潜艇水下航行可达1200米。,在这短短的一分钟里，全世界都在发生变化。250万人寄信，有5000个 以上的婴儿诞生；地球绕太阳转动 1000英里,一寸光阴一寸金， 寸金难买寸光阴。,珍惜每分钟，因为时间是由分秒积成的，,11,12,10,1,3,4,5,6,9,8,7,2,从四时开始数。,4时,4:00,11,12,10,1,3,4,5,6,9,8,7,2,从四时开始数。,4时 5分,4:05,11,12,10,1,3,4,5,6,9,8,7,2,从四时开始数。,4时30分或4时半,4:30,11,12,10,1,3,4,5,6,9,8,7,2,从四时开始数。,4时45分,4:45,时针走过数字4，分针从12起走了多少个小格，就是4时多少分。,8:05,1:25,6:50,认一认,我发现了：,读出一个时间，要根据时针和分针的位置来共同确定，时针过了数字几，就是几时多，分针走了多少格，就是几分。,应用拓展，巩固新知,做一做。,问题：你能准确写出每个钟表所表示的时间吗？,7:30,7:40,8:00,10:45,9:55,6:05,1:20,应用拓展，巩固新知,9时30分,9：30,6时40分,6：40,8时35分,8：35,我们要合理安排时间。