九年级(上)物理9《大气压_气体压强与流速的关系》（Grade nine (on) the 9 physical atmospheric pressure _ gas pressure and flow rate relationship）.docVIP

九年级(上)物理9《大气压_气体压强与流速的关系》（Grade nine (on) the 9 physical atmospheric pressure _ gas pressure and flow rate relationship） The relation between atmospheric pressure, gas pressure and velocity: Xu Fenglin 1.. The proof of atmospheric pressure and the explanation of phenomena; Determination of 2. atmospheric pressure and its influencing factors; Variation law of 3. gas pressure with flow velocity and its application. Two, focus and difficulty explain (1) atmospheric pressure The atmosphere around the earth at 1. atmospheric pressure is collectively called the atmosphere. Atmospheric pressure is called atmospheric pressure, referred to as atmospheric pressure. (1) the hemispheric experiment in Fort Hood strongly demonstrated the presence of atmospheric pressure. (here are the pictures, please refer to attachment 01.bmp.) As shown in Figure 1, it is the scene of the hemispheric experiment in Fort hood. In Germany, in the square of Heidelberg, in 1654, there was a famous experiment on the hemispheric hemispheres. The copper hollow hemisphere two radius of about 0.2m together, out of the air inside, pull the two hemispheres in the opposite direction with two horses, almost do not open. As shown in Figure 2 [pic00000.bmp] (here are the pictures, please refer to attachment 01.bmp.) (2) the following three cases are related to atmospheric pressure: (1) the plastic hook of the sucker attached to the smooth wall, can withstand a certain tensile force without falling off. When sipping a drink with a straw, atmospheric pressure causes the drink to rise into the mouth. The iron bucket and put some water, boil after the opening of the block, and then poured cold water, iron was squashed. [pic00001.bmp] [pic00002.bmp] [pic00003.bmp] The value of 2. atmospheric pressure (1) Tori demolition experiment: the Tori demolition experiment was the first to test atmospheric pressure. This experiment measured atmospheric pressure to support 760mm height mercury column. [pic00004.bmp] [pic00005.