六年级数学下册课件-3.1.3 圆柱的体积公式的推导12-人教版(共13张PPT).pptx

情境导入情境导入温故知新温故知新温故知新温故知新长长v =a b hv3正正=a温故知新温故知新长长v =a b hv3正正=aV=S h底底温故知新温故知新V=S h底底V=S h底底?温故知新温故知新S=r探究新知探究新知探究新知探究新知V=S h底底 像长方体、正方体、圆柱体像长方体、正方体、圆柱体这种立体图形都叫做直柱体这种立体图形都叫做直柱体。应用新知应用新知d=30cmh=20cm应用新知应用新知r=302=15cmS底底=r =3.1415 =706.5（cm）V=S底底h=706.520=14130（cm）d=30cmh=20cmV=S底底h=rh8 8等分等分1616等等分分128128等分等分回顾反思回顾反思