论文部分内容阅读
在一定条件下,运用数列解决物理问题,可以显现物理现象的全过程,反映物理现象的变化趋势,揭示物理现象的变化规律。使学生从有限中认识无限;从近似中认识精确;从量变中认识质变。中学物理教学中,这样的例子很多。本文仅举几种常见的类型。一、运用数列的通项公式求经任一次变化后的物理量例1 机械抽气机的抽气是利用体积膨胀来降低气压的。如果被抽容器的容积是抽气机活塞筒活动容积的2倍,问在抽气动作20次后被抽容器内的压强变为多少?设大气压强为76厘米水银柱高,抽气过程中气体的温度不变。
Under certain conditions, the use of series to solve physical problems can reveal the whole process of physical phenomena, reflect the changing trend of physical phenomena, and reveal the changing laws of physical phenomena. Make students understand the infinite from the limit; understand the accuracy from the approximation; understand the qualitative change from the quantitative change. There are many examples of this in middle school physics teaching. This article only mentions several common types. First, use the general equation of the series to calculate the physical quantity after any change. Example 1 The pumping of a mechanical aspirator uses volume expansion to reduce the pressure. If the volume of the pumped vessel is 2 times the volume of the pumping cylinder, ask how much the pressure in the pumped vessel will be after 20 pumping operations. The atmospheric pressure is 76 cm Hg. The temperature of the gas does not change.