Re: [分享] 近物題目
※ 引述《o0footman0o (腳男)》之銘言：
※ 引述《flyevilwind (黃不黃)》之銘言：
: P.2
: At what speed would you have to move past a 10-cm ruler so that you
: could observe its length to be 5 cm?
應在何速度下穿過一10公分之直尺，你將測量出其長度為5公分
ans: ──────
5 = 10 * /(1-v^2/c^2) => v = (3^0.5/2)*c ~ 0.866c
v
: P.3
: A meter stick moves parallel to its axis with speed 0.96c relative to you.
: What would you measure for the length of the sticks? How long does it take
: for the sticks to pass you?
一計量棒平行其軸以相對你為0.96倍光速的速度移
^^^^^^
一公尺長的
試問：你將測量到的長度為多少？在計量棒經過你時走了多遠？
^^^^ ^^^^^^^^
(只是一個長1公尺的普通棒子^^)(應該是花了多少時間，how long是多久的意思)
ans: ─────────
L' = 1 * /(1-(0.96c)^2/c^2) = 0.28 公尺
v
_
τ= Δt' = L'/ v = 0.28(m)/0.96*3*10^8(m/s) = 9.72*10^-10 (s)
: Q3
: A person with a stopwatch stands on the platform of a train station marking
: the arrival of the head of the train at one end of the platform and the tail
: of the train at the other end of the platform. This is not a good operational
: way to measure the possible simultaneity of the arrivals of the head and tail
: in the rest frame of the platform. Why is that? What would be the right way to
: measure the possibe simultaneity?
: 作業要交p.2和p.3
: Q3不用交但是要想一下
: 題目有打錯跟我說
: 話說這是我第一次發文耶XD
自己翻譯的 求 解........
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哈 無聊充文章數， 有錯不要怪我 隨手翻以前筆記看的
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※ 編輯: liweits 來自: 61.223.227.154 (09/28 03:05)
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