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1、第二課：物理學家費曼、能量守恒費曼集大成的理論物理學家費曼19181988偉大的物理表演藝術家因創(chuàng)立量子電動力學（Quantum electrodynamics QED）而獲得1965年諾貝爾物理學獎。曾參與美國曼哈頓計劃，設計了第一顆原子彈費曼鼓手費曼費曼畫家費曼一本好書中文譯本：別鬧了，費曼先生！摘錄一（年幼的費曼與父親閱讀百科全書）：We would be reading, say, about dinosaurs. It would be talking about theTyrannosaurus rex and it would say something like, This d

2、inosaur is twenty-five feet high and its head is six feet across. My dad would stop reading and say, Now, lets see what that means. That would mean that if he stood in our front yard, he would be tall enough to put his head through our window up here. (We were on the second floor.) But his head woul

3、d be too wide to fit in the window. 摘錄一（續(xù)）Everything he read me he would translate as best he could into some reality. It was very exciting and very, very interesting to think there were animals of such magnitude-and that they all died out, and that nobody knew why. I wasnt frightened that there wou

4、ld be one coming in my window as a consequence of this. But I learned from my father to translate: everything I read I try to figure out what it really means, what its really saying.摘錄二I had a scheme, which I still use today when somebody is explaining something that Im trying to understand: I keep

5、making up examples. For instance, the mathematicians would come in with a terrific theorem, and theyre all excited. As theyre telling me the conditions of the theorem, I construct something which fits all the conditions. You know, you have a set (one ball)-disjoint (two halls). Then the balls turn c

6、olors, grow hairs, or whatever, in my head as they put more conditions on. Finally they state the theorem, which is some dumb thing about the ball which isnt true for my hairy green ball thing, so I say, False!費曼告訴我們如何學習學習新知的時候，要轉化成自己熟悉的、具體的事物。如何學習費曼物理學講義I？“大學物理I”希望大家學到什么？1：熟讀課本。中文講義看不懂？請看英文原版。2：適量練

7、習 。講義配套習題集可從網(wǎng)上下載。3：勤思多問。充分利用互聯(lián)網(wǎng)（維基百科，某度百科）?！按髮W物理I” 拓展視野，了解自然。能量守恒能量守恒 對宇宙最基本的信念，或，宇宙最基本的事實?；拘拍?各種能量的表達形式，轉化規(guī)律。正如幾何學一樣，從簡單的“公理”出發(fā)（比如平行線永不相交等）推導出復雜的定理。勢能（potential energy）利用能量守恒，求解物理問題?！疤撐灰啤保╲irtual displacement）動能能量守恒的第一次精彩演出如何得到動能的表達形式？圖片取自： http:/www.aps.org/publications/apsnews/200908/zerogravity.cfm其他形式的能量其他物理量的守恒關系動量守恒角動量守恒電荷守恒輕子數(shù)守恒重子數(shù)守恒宇稱(parity)守恒（因理論預言在某些核物理過程中宇稱不守恒，楊振寧與李政道先生獲得1957年諾貝爾獎。該預言由華人女物理學家吳健雄實驗證明。）