过堂风

当居室前后窗子打开时，“过堂风”会把侧面墙上的衣柜门      （选填“吹开”或“关紧”），可以用物理知识：气体流速大的地方压强________来解释。

当居室前后窗子都打开时，“过堂风”有时会把居室侧面摆放的衣柜门吹开，这是因为       ；将糖分别放在热水和冷水中，热水变甜的更快一些，这是因为            。

当居室前后窗子都打开时，“过堂风”会把居室侧面摆放的衣柜门吹开，这是因为___\_；将糖分别放在热水和冷水中，热水变甜的更快一些，这是因为______．

当居室前后的窗子打开时，“过堂风”会把侧面墙上的衣柜门吹开，这是因为柜外的空气流速___\_，衣柜内的空气压强______衣柜外的空气压强（填“大于”、“小于”或“等于”）．

用吸管吸饮料时，在___\_的作用下使饮料上升到嘴里；居室前后两面的窗子打开时，“过堂风”会把居室侧面的衣柜的门吹开，这主要是由于衣柜门外表面的空气流速较大，压强______（选填“较大”或“较小”）造成的．

当居室前后两面的窗子都打开时，“过堂风”会把居室侧面摆放的衣柜的门吹开．这一现象涉及到的主要物理知识是：在气体和液体中，______．请再举两个应用这一物理知识的例子：
（1）______；
（2）______．

能够说明流体压强与流速的关系的现象是（）

A．高度越高，大气压强越小

B．当居室前后两面的窗子都打开时，“过堂风”会把居室侧面摆放的衣柜的门吹开

C．用吸管吸饮料时，饮料会上升到嘴里

D．塑料挂钩的吸盘贴在光滑的墙面上，能承受一定的拉力而不脱落

下列实例中，不能利用气体或液体压强与流速关系解释的是（）

A．在火车进、出站台时，乘客必须站在安全线以外

B．“过堂风”会把居室中侧面摆放的衣柜门吹开

C．用气筒给篮球打气，将气筒活塞往下压时感觉吃力

D．汽车在马路上快速驶过以后，马路两边的树叶会随风飘动

Firefighters ane often asked to speak to school and community groups about the importance of fine safety, particularly fire prevention and detection. Bccause smoke detectors reduce the risk of dying in a fire by half. firefighters often provide audiences with information on how to install these protectivc devices in their homes.
Specifically, they tell them these things: A smoke detector should be placcd on each floor of a home. While sleeping, people are in particular danger of an emergent fire、 and there must he a dctcctor outside each sleeping area. A good site for a detecior would he a hallway that runs between living spaces and bedrooms.
Because of the dead-air space that might be missed by hot air bouncing around above a fire, smoke detcctors should be installed either on the ceiling at least four inches from the nearest wall, or high on a wall at least four, but no further than twelve, inches from the ceiling.
Deteccors should not be mounted near windows, entrances, or other places where drafts （过堂风) might direct the smoke away from the unit. Nor should they be placed in kitchens and garages, where cooking and gas fumes are likely to cause false alarms.
One responsibility of a firefighter is to______.
A．install smoke detectors in residents homes
B．check if smoke detectors are properly installed
C．develop fire safety programs for schools
D．speak to residents about how to prevent fires