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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 Current and the coulomb？

又称： electric current · ampere · coulomb

Definition 12.1 High School Physics · 第 12 章 — Electric Circuits and Power

An electric current is an ordered flow of charge (electrons, in a metal). Its intensity $I$ , in amperes ( $\mathrm{A}$ ), is the charge passing through a cross-section of the wire per second: a steady current $I$ flowing for a time $t$ transports the charge

q = I\,t ,

in coulombs ( $\mathrm{C}$ ), with $1\,\mathrm{C} = 1\,\mathrm{A}\,\mathrm{s}$ . The elementary charge is $e = 1.6 \times 10^{-19}\,\mathrm{C}$ . Current is measured by an ammeter, inserted in series.

示例

Example 12.2 (Lightning versus phone)

A lightning stroke carries some $3.0 \times 10^{4}\,\mathrm{A}$ for about $1.0 \times 10^{-4}\,\mathrm{s}$ : $q = 3.0\times10^{4} \times 10^{-4} = 3.0\,\mathrm{C}$ . Your phone, at $2.0\,\mathrm{A}$ , moves the same charge every $1.5$ seconds.

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