26.1 Some important discoveries at the end of the 20th century a. Measured the charge of the cathode rays; b. Make a static electric deflection of the cathode rays; . Measured the charge to mass ratio of the cathode rays;

1. The discovery of electrification OThe phenomenon of electrification Glass rod is rubbed with silk-positive Amber rod is rubbed with fur--negative

8—3电场强度 一、静电场 实验证实了两静止电荷间存在相互作用的静电力,但其相互作用是怎样实现的?

I. Choose the Correct Answer . real engine has an efficiency of33%. The engine has work output of2 4J4 per cycle.how much heat energy is extracted from the high-temperature reservoir per cycle? (D) (A)8J

8—6电势能 一 静电场力所做的功

一.单缝夫琅和费衍射 1.装置:

一.单缝夫琅和费衍射 二.圆孔夫琅和费衍射 三光栅夫琅和费衍射 四.晶格衍射(X光衍射)

一.单缝夫琅和费衍射 二.圆孔夫琅和费衍射 三.光栅夫琅和费衍射

一、冲量(impulse) 牛顿定律的变化形式:

一、万有引力、重力、弹性力作功的特点 (1)万有引力(universal gravitation)作功 以m为参考系,m的位置矢量为r. m对m的万有引力为