Room B-204: Student Laboratory Rules
Any experimental work after 5 p.m. must be booked with Dr. Hsu two days in advance, and no student may stay in the room alone. Broken glass goes into the red box, never into the paper bin.
B-204 室：學生實驗室規則
下午五點以後的任何實驗工作，必須提前兩天向徐博士預約，且學生不得單獨留在室內。破掉的玻璃要丟進紅色箱子，絕不可丟入紙類回收桶。
Dear Professor Yang,
My name is Kevin Chou, and I am a second-year student in chemistry. I heard your talk about clean water last month, and I would like to ask whether your laboratory takes student helpers during the summer.
I spent one term working with Dr. Lin, mostly washing glassware and recording data, so I know how slow real research can be.
I can offer four full days a week from July 1 to August 31. I have attached my grades and a one-page report on a simple experiment I designed myself. If there is no room in your group this year, I would still be grateful for advice on what to read.
Yours sincerely,
Kevin Chou
楊教授您好：
我叫周凱文，是化學系二年級的學生。上個月我聽了您關於乾淨水源的演講，想請問您的實驗室暑假是否收學生助手。
我曾在林博士那裡工作一個學期，主要是清洗玻璃器皿和記錄數據，所以我知道真正的研究有多慢。
我可以從七月一日到八月三十一日，每週提供四個整天。我附上了我的成績單，以及一份一頁的報告，內容是我自己設計的一個簡單實驗。如果今年您的團隊沒有名額，我仍然很感謝您能給我一些閱讀方面的建議。
敬祝 教安
周凱文
An atomic clock in a locked room in Colorado loses less than one second in a hundred million years. Few people need that kind of accuracy, yet almost everyone uses it, because every phone map depends on satellites that carry such clocks.
The scientific idea behind them is simple. Atoms of one metal always take exactly the same tiny amount of time to change their state, so counting those changes is more reliable than counting the swings of a pendulum.
Engineers are now building a clock that is ten times more accurate. Their aim is not to be on time for dinner, but to measure how gravity slightly slows time itself.
科羅拉多州一間上鎖房間裡的原子鐘，一億年才會差不到一秒。很少人需要這種精準度，卻幾乎人人都在使用它，因為每一個手機地圖都仰賴搭載這種時鐘的衛星。
它背後的科學原理很簡單。同一種金屬的原子改變狀態所需的極短時間永遠完全相同，因此計算這些變化，比計算鐘擺的擺動更可靠。
工程師目前正在打造一個精準度再高十倍的時鐘。他們的目標不是為了準時吃晚餐，而是要測量重力如何讓時間本身稍微變慢。
Two classes repeated the same experiment: they dropped a ball from a height of one meter onto four surfaces and measured how high it bounced.
| Surface | Class A | Class B |
|---|---|---|
| Wood | 62 cm | 58 cm |
| Glass | 71 cm | 74 cm |
| Carpet | 24 cm | 21 cm |
| Sand | 6 cm | 5 cm |
Each figure is the average of ten drops. The two classes used balls of the same weight.
兩個班級重複了同一個實驗：他們把球從一公尺高處落到四種表面上，並測量彈起的高度。
| 表面 | A 班 | B 班 |
|---|---|---|
| 木頭 | 62 公分 | 58 公分 |
| 玻璃 | 71 公分 | 74 公分 |
| 地毯 | 24 公分 | 21 公分 |
| 沙地 | 6 公分 | 5 公分 |
每個數字都是十次落球的平均值。兩班使用的球重量相同。