📚 Year 11 Edexcel Physics: Formula & Theorems Quick Reference Handbook | Year 11 Edexcel 物理：公式定理速查手册
This quick reference handbook gathers every key formula and theorem you need for the Year 11 Edexcel Physics course. Each entry is presented with clear variable definitions and is followed by a Chinese explanation, helping you revise efficiently for your GCSE exams. Whether you are practising past papers or making flashcards, this guide ensures you have the essential equations and concepts at your fingertips.
这本速查手册汇总了 Year 11 Edexcel 物理课程所需的全部核心公式和定理。每一条公式都配有清晰的变量定义和中英文双语解释，帮助你高效备考 GCSE。无论是刷真题还是制作记忆卡片，本指南都能让你随时调用最关键的方程和概念。
1. Key Concepts of Physics | 物理关键概念
All measurable quantities in physics are expressed in SI units. Knowing the base units and standard prefixes allows you to convert measurements and write very large or small numbers using powers of ten.
物理学中所有可测量的量都用国际单位制 (SI) 表示。掌握基本单位与标准前缀，你可以进行单位换算，并用 10 的幂次表示极大或极小的数字。
| Quantity | Unit | Symbol |
|---|---|---|
| length | metre | m |
| mass | kilogram | kg |
| time | second | s |
| electric current | ampere | A |
| temperature | kelvin | K |
| amount of substance | mole | mol |
fixes include milli (m, 10⁻³), centi (c, 10⁻²), kilo (k, 10³) and mega (M, 10⁶). Standard form is used to simplify numbers, e.g. 3.0 × 10⁸ m/s for the speed of light.
上表列出了六个基本物理量及其 SI 单位。其他所有单位，如力的单位牛顿 (N)，均由这些基本单位导出。常用的倍数前缀有毫 (m, 10⁻³)、厘 (c, 10⁻²)、千 (k, 10³) 和兆 (M, 10⁶)。标准形式用于简化数字，如光速写作 3.0 × 10⁸ m/s。
2. Motion and Forces | 运动与力
This section covers the equations of uniformly accelerated motion, Newton's laws, momentum, moments, and other force-related formulas. Knowledge of these relationships is essential for solving problems about moving objects and equilibrium.
本节涵盖匀加速运动方程、牛顿定律、动量、力矩以及其他与力相关的公式。理解这些关系对于解决物体运动和平衡问题至关重要。
Equation of motion 1: t = time. This links velocity, acceleration and time for a uniformly accelerating object.
运动方程 1： v = u + a t，v 为末速度，u 为初速度，a 为恒定加速度，t 为时间。它将匀加速物体的速度、加速度和时间联系起来。
v² = u² + 2 a s
l velocity, initial velocity, acceleration and displacement s (distance moved in a straight line). Useful when time is not known.
方程 v² = u² + 2 a s 将末速度、初速度、加速度和位移 s（沿直线移动的距离）关联起来。当时间未知时非常有用。
s = (u + v) / 2 × t
This equation gives the displacement s when average velocity is multiplied by time. It is derived from the area under a velocity-time graph.
该方程用平均速度乘以时间得到位移 s。它源自速度-时间图下的面积。
F = m a
Newton's second law: the resultant force F (in newtons) acting on an object is equal to its mass m (in kg) times its acceleration a. This is the fundamental link between force, mass and acceleration.
牛顿第二定律：作用在物体上的合力 F（单位牛顿）等于物体质量 m（单位千克）乘以加速度 a。这是力、质量和加速度之间的基本关系。
W = m g
mes gravitational field strength g (on Earth, g ≈ 9.8 N/kg). Weight always acts downwards.
物体的重量 W 是它受到的重力，等于质量 m 乘以引力场强 g（地球上的 g 约为 9.8 N/kg）。重量方向始终竖直向下。
p = m v
Momentum p (kg m/s) is the product of mass and velocity. Momentum is a vector quantity; its direction is the same as the velocity. Higher Tier only.
动量 p（单位 kg m/s）是质量与速度的乘积。动量是矢量，方向与速度相同。仅限高阶内容。
F = Δp / Δt
Newton's second law in terms of momentum: the force acting on an object equals the rate of change of its momentum. This version is used for collisions and safety features.
动量形式的牛顿第二定律：作用在物体上的力等于其动量的变化率。这一形式常用于分析碰撞和安全装置。
M = F d
res (N m), it determines whether an object will rotate. Principle of moments: for a balanced object, sum of clockwise moments = sum of anticlockwise moments.
力矩 M（转动效果）等于力乘以从支点到力作用线的垂直距离 d。单位为牛顿米 (N m)，它决定物体是否会转动。力矩原理：平衡时，顺时针力矩之和等于逆时针力矩之和。
F = k x
Hooke's Law: the extension x (in metres) of a spring is directly proportional to the applied force F, provided the elastic limit is not exceeded. k is the spring constant (N/m), representing stiffness.
胡克定律：在不超过弹性限度的条件下，弹簧的伸长量 x（米）与施加的力 F 成正比。k 是弹簧常数（N/m），表示弹簧的刚度。
p = F / A
Pressure p (in pascals, Pa) is the force F applied per unit area A. A force applied over a smaller area produces a larger pressure. This applies to both solids and fluids.
压强 p（单位帕斯卡，Pa）是单位面积 A 上施加的力 F。作用力一定时，受力面积越小，压强越大。固、液、气体均适用。
p = h ρ g
liquid density (kg/m³) and g is the gravitational field strength. This is independent of container shape. Higher Tier.
对于液柱，深度 h 处的压强为 p = h ρ g，其中 ρ 是液体密度 (kg/m³)，g 是引力场强。该公式与容器形状无关。高阶内容。
3. Work, Energy and Power | 功、能量与功率
Energy can be stored in different forms and transferred between stores. The following equations allow you to calculate kinetic energy, gravitational potential energy, elastic potential energy, work done, and the rate of energy transfer (power).
能量可以不同形式储存并在不同储能库之间转移。以下公式可用于计算动能、引力势能、弹性势能、做功以及能量转移速率（功率）。
Eₖ = ½ m v²
The kinetic energy Eₖ (in joules) of a moving object depends on its mass m and the square of its speed v. Doubling the speed quadruples the kinetic energy.
运动物体的动能 Eₖ（焦耳）取决于其质量 m 和速度 v 的平方。速度加倍，动能变为原来的四倍。
ΔEₚ = m g Δh
The change in gravitational potential energy ΔEₚ is the product of mass m, gravitational field strength g, and the change in vertical height Δh. This energy is transferred when an object is lifted against gravity.
引力势能的变化量 ΔEₚ 等于质量 m、引力场强 g 和垂直高度变化 Δh 的乘积。当物体被克服重力抬高时，能量发生转移。
Eₑ = ½ k x²
The elastic potential energy Eₑ stored in a stretched (or compressed) spring depends on its spring constant k and the square of its extension x. This assumes Hooke's Law holds. Higher Tier.
储存在被拉伸（或压缩）弹簧中的弹性势能 Eₑ 取决于弹簧常数 k 和伸长量 x 的平方。该公式在胡克定律成立的前提下使用。高阶内容。
W = F d
Work done W (in joules) is calculated by multiplying the force F applied by the distance d moved in the direction of the force. One joule is one newton-metre. Work done often equals the energy transferred.
做功 W（焦耳）等于施加的力 F 乘以物体在力的方向上移动的距离 d。1 焦耳相当于 1 牛顿米。做功的量常等于转移的能量。
P = E / t or P = W / t
energy. It is calculated by dividing energy E or work W by the time t taken. 1 W = 1 J/s.
功率 P（瓦特）是做功或转移能量的速率，等于能量 E 或功 W 除以所用时间 t。1 W = 1 J/s。
Efficiency = (Useful energy output / Total energy input) × 100%
Efficiency measures how well a device converts input energy into useful output energy. It can be expressed as a decimal or a percentage. No device can be 100% efficient due to energy dissipated (often as heat).
效率衡量装置把输入能量转化为有用输出能量的程度，可用小数或百分比表示。由于总会有能量耗散（通常为热），任何装置效率都不可能达到 100%。
4. Waves and the Electromagnetic Spectrum | 波与电磁波谱
Waves transfer energy without transferring matter. The key relationships linking wave speed, frequency, wavelength and period apply to both transverse waves (e.g. light) and longitudinal waves (e.g. sound). The electromagnetic spectrum arranges all EM waves by wavelength and frequency.
波传递能量而不传递物质。描述波速、频率、波长和周期的重要关系式对横波（如光）和纵波（如声）均适用。电磁波谱根据波长和频率排列所有电磁波。
