※ 引述《lilin (Instant Aura)》之銘言： 前刪 : 請大家參考看看。 : 我自己的印象是，在一般文獻中dynamics常和kinetics混用，mechanics則是統稱。 這兩個怎麼會混用啊..... 要說也是Kinematics和Kinetics這兩個用dynamics來統稱 而且在Beer & Johnston的動力學課本裡面一開就解釋過Dynamics是啥了 課本一開始的地方沒有跳過沒看的話應該是不會搞錯這兩個詞才對 把以前的文翻出來貼 （第三版，P.584） Dynamics includes: 1. Kinematics, which is the study of the geometry of motion. Kinematics is used to relate displacement, velocity, acceleration, and time, without reference to the cause of motion. 2. Kinetics, which is the study of the relation existing between the forces acting on a body, the mass of body, and the motion of body. Kinetics is used to predict the motion caused by given forces or to determine the forces required to produce a given motion. Kinematics是探討的運動各物理量（但是不會出現力與質量）之間的關係 而此關係的狀態會一直持續，不會改變 Kinetics則是探討運動與力的關係（還會有質量影響） 而此關係為預測未來可能會出現的變化 最好判斷的就是使用NT 2nd Law的就是Kinetics，因為Kinetics才會提到力 力會改變運動狀態，要計算出被改變的運動狀態 無使用到NT 2nd Law的就是Kinematics，所以運動狀態將持續不改變 -- Deserves death! I daresay he does. Many that live deserve death. And some die that deserve life. Can you give that to them? Then be not too eager to deal out death in the name of justice, fearing for your own safty. Even the wise cannot see all ends. Gandalf to Frodo --

※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 61.225.198.127 ※ 編輯: Gwaewluin 來自: 61.225.198.127 (08/12 18:29)