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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 Characteristic; resistor; Ohm’s law？

Definition 6.7 University Physics — Year 1 · 第 6 章 — DC Circuits: Kirchhoff’s Laws and Theorems

The characteristic of a dipole is the curve $i(u)$ (or $u(i)$ ) it imposes. A resistor has a linear characteristic through the origin, Ohm’s law

u = R\,i \qquad (\text{receiver convention}),

$R$ being its resistance (ohms, $1\,\Omega = 1\,\mathrm{V}/\mathrm{A}$ ) and $G = 1/R$ its conductance (siemens). It receives $p = Ri^2 = u^2/R \geq 0$ , dissipated as heat (Joule effect). A wire of length $\ell$ , cross-section $S$ and resistivity $\rho$ has $R = \rho\ell/S$ .

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