※ 引述《outlook2 (容)》之铭言： : ※ [本文转录自 StarTrek 看板] : 作者: outlook2 (容) 看板: StarTrek : 标题: 两题物理问题 : 时间: Wed Jun 4 01:13:19 2008 : Modern Problems of Classical Electrodynamics : Special Relativity 以下都是个人直觉 : (1) : Data and the emperor of Ferengi are locked in a deadly battle of Wheel of : Fortune starring Vanna White, who has been travelling around the earth at : nearly the speed of light for centuries to stay young. Vanna is in an orbit : 100 light second from earth with Data and the Ferengi nearby, while the host, : Darth Vader, on loan from another studio, is on earth. When Vanna gives the : contestants the last question, the Ferengi emperor attempts to cheat by : speeding towards the Earth at a speed of 0.99c while he is thinking, so that : when he radios his answer to Darth Vadar, it will arrives first. However, he : forget that when travelling at nearly the speed of light, his thinking slows : down due to time dilation. Data takes 10 seconds and the Ferengi takes 12 : seconds to answer, each according to their own clock, so it takes, for : example, 110s for Data's answer to reach Darth Vadar. : Question: Does the cheating pay? That is, will the emperor's answer reach : earlier? Please present all the calculations and derivations. 时间的迟滞只发生在"""观察者"""所看到相对运动中的"被观察者"身上 现在,观察者是Vadar.如果Data是跟着Vadar运行,那它们的相对运动是非常小的,也就是 10秒钟没有延时. Ferengi自己的计时是12秒,架设在没有相对关系的空间中,他跑了12光秒,Vadar也绕行 轨道12光秒,非常小的轨道弧度,为方便计算,我假设Vadar几乎没有运动,只有Ferengi对 他做0.99c的相对运动. 不必考虑相对论,单是考虑Ferengi移动12秒,就已经话了12秒.之後Ferengi的答案也花 了近12秒才来到Vadar这边.也就是至少24秒的做答时间... : (2) : A truce has been arranged between the Federation and the Romulans. According : to the treaty, the first captain to fire in an engagement is EXECUTED! The : evidence is as below. Captain Picard suddenly detects a Romulan ship as it : begins to uncloak itself, and realized that it is hostile! The strength of : the emmision shows that the Romulan ship is 1000 light second away so it must : have fired its photon torpedo (assume it travels at light speed). The : Enterprise immediately fired its own photon torpedo. 100 seconds later, : Enterprise is hit. Some time later (in the coordinate system of Enterprise), : the Romulan ship was also hit. Both ships travels at constant speed during : the engagement. Both ships were disabled, and a court of inquiry was : convented. The two captains agreed on the facts above, but each argued, : based on their e-logs, that the other fired first. Is it possible that both : are telling the truth, at least in their respective coordinate system? If : so, what is the minimum speed between them and what is the direction (either : toward each other or away from each other)? If not, who shall be executed? 依我的直觉, 假设他们同时在距离1000光秒,第0秒时发射 如果没有相对运动,发射讯号在1000秒後到达,那他们不可能预先发射了 如果相对以光速靠近,讯号在500秒後到达,在这500秒内,他们会看到对方船上 负一千~0秒 所发生的事 如果以2倍光速靠近,讯号在1000/3=333秒後到达.这333秒,观察对方船上 -1000~0秒事件 999倍光速,讯号在1000/(999+1)=1秒後..仍然不是在第0秒之前....orz ______________________________________________________________ 接下来和上面的问题无关. 我个人认为.以为光速运动就能让时间无限延长,只是个天大的笑话,纯属个人信念 1st,当在'被观察者'远离时,'观察者'看到发生在'被观察者'身上的事件,例如一个呼吸 就是好久好久.但是要考虑'被观察者'在准备返回时做减速运动,至反向的光速返回,这时 大部分的时间就会被补偿回来(逆时间延长!).然後一直到回到出发点,就会全补偿回来... 2nd,相对论既然自称为相对论,说明的不只是时间空间的相对关系,也是要考虑到运动者的 相对关系,所以我一开始就说了'观察者'和'被观察者'.相对而言,两者关系完全可以对调 那如果光速运动确实让人不老化,就会有年轻的我看年老的你,说怎麽我变老了,你却依然 年轻 相对论告诉我们的是,我们无法为光速运行的物体加速,因为它的相对质量是无限大 -- 以上是普物相对论章节考试趋近0分的家伙的意见. 欢迎挑战 XDD --

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