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1 Markets I: The Ecosystem and Exchange-Traded Markets市场在线 2 Markets II: Rates, FX and Credit市场在线 3 Markets III: Commodities, Energy and Crypto市场在线 4 Quantitative Methods方法在线 5 Derivatives and Volatility衍生品在线 6 Rates, Credit, XVA and Risk利率、信用与风险在线 7 Research Craft: Predictors, Backtests, Measurement, Portfolios研究在线 8 Strategies I: Equities and Futures策略在线 9 Strategies II: Volatility, Relative Value, Macro and the Bank Desks策略在线 10 Microstructure and Execution交易执行在线 11 Market Making and High-Frequency Trading做市在线 12 Machine Learning for Markets机器学习在线 13 Low-Latency Software技术在线 14 Networks, Hardware and Trading Infrastructure技术在线 15 Research, Data and Risk Platforms技术在线 16 The Desk and the Firm公司运营在线 17 The Industry: Firms, Roles and Careers职业发展在线 18 Interviews I: Maths, Probability and Speed职业发展在线 19 Interviews II: Markets, Trading Games and the Final Round职业发展在线 20 Interviews III: Code职业发展在线

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Physics · 术语表

什么是 Centimetre and metre？

又称： centimetre · metre

Definition 7.6 Primary & Middle School Physics · 第 7 章 — Measuring Length

The centimetre (written $\mathrm{cm}$ ) is a small unit of length, about the width of a fingernail; it is printed on every ruler. The metre (written $\mathrm{m}$ ) is a big unit, exactly $100$ centimetres, the length of a very big step. These units are the same for everyone on Earth: your $20\,\mathrm{cm}$ and my $20\,\mathrm{cm}$ are exactly equal.

A metre stick: one hundred centimetres in a row. The marks let us count them quickly instead of one by one.

示例

Example 7.8 (Which unit for which job?)

Small things like a beetle, a stamp or your hand are measured in centimetres. Big things like a corridor, a bus or a swimming pool are measured in metres: the pool is $25\,\mathrm{m}$ long — imagine counting that in fingernail-widths! Choosing a sensible unit is half the work of measuring.

Example 7.9 (Estimate, then check)

Before measuring, players guess: how long is the kitchen table? Papa says $2\,\mathrm{m}$ , Lina says $1\,\mathrm{m}$ and a bit. Then the metre stick decides: $1\,\mathrm{m}$ and almost a half — point for Lina. Guessing first trains your eye; measuring keeps everyone honest.

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