CAIE考试局官网发布了新的考试大纲，适用于2022—2024年的考试，今天小渊就为各位同学解读一下2022—2025新考纲A-Level物理AS部分的一些改动：
新增的知识点
Increase
Density and pressure密度与压强
calculate the upthrust acting on an object in a fluid using the equation F = ρgV (Archimedes’ principle)
在密度和压强 Density and pressure部分，新增加了Upthrust计算公式，这里需要进一步理解到upthrust=ρgV=weight of fluid displaced，也就是等于排开液体的重力。
Stress and strain应力和应变
understand and use the terms load, extension, compression and limit of proportionality
除了旧大纲要求的elastic limit(弹性极限)之外，新大纲明确要求掌握limit of proportionality(比例极限)。
Electromagnetic spectrum电磁波
recall that wavelengths in the range 400–700 nm in free space are visible to the human eye.
电磁波这部分虽然我们在往常学习的时候要求掌握各个波段wavelength的大致范围，新大纲明确了人眼能看到的可见光波段：400-700nm。
Polarisation波的偏振现象
1.understand that polarisation is a phenomenon associated with transverse waves
2. recall and use Malus’s law (I = I0 cos2θ ) to calculate the intensity of a plane polarised electromagnetic wave after transmission through a polarising filter or a series of polarising filters
waves波这一部分新增加了polarisation，波的偏振，以往的剑桥考试局ALevel部分对polarisation不做要求，这部分内容的增加，让学生从更多的方面来理解光波。
Resistance and resistivity电阻率
explain that the resistance of a filament lamp increases as current increases because its temperature increases
understand that the resistance of a thermistor decreases as the temperature increases (it will be assumed that thermistors have a negative temperature coefficient)
电学部分，以往对filament lamp和thermistor电阻随温度的变化是需要掌握的，能够运用resitance和温度的变化趋势来解释某个电路中power、resistance等等变化，但是并没有在大纲里明确写明这两条要求。
understand that the resistance of a light-dependent resistor (LDR) decreases as the light intensity increases
新增加了光敏电阻LDR的resistance随光照强度的变化规律。
Potential dividers分贝器
understand the use of a galvanometer in null methods
explain the use of thermistors and light-dependent resistors in potential dividers to provide a potential difference that is dependent on temperature and light intensity
早年一点的历年题有关于a galvanometer in null methods的计算题和选择题，在新大纲中新明确了对这个点的掌握要求。
热敏和光敏电阻要求掌握在potential divider中的应用，这很明显是简答题的考察。
Atoms, nuclei and radiation原子、核和辐射
understand that α-particles have discrete energies but that β-particles have a continuous range of energies because (anti)neutrinos are emitted in β-decay
represent α- and β-decay by a radioactive decay equation of the form
use the unified atomic mass unit (u) as a unit of mass
Particle这部分要求掌握alpha particle所具有的能量是不连续的，而β粒子的能量是连续的。关于11和12两条内容授课均有讲述，这次在新大纲中做了明确的要求。
Fundamental particles基本粒子
recall and use the charge of each flavour of quark and understand that its respective antiquark has the opposite charge (no knowledge of any other properties of quarks is required)
understand that a hadron may be either a baryon (consisting of three quarks) or a meson (consisting of one quark and one antiquark)
基本粒子部分新增了meson;需掌握hadron可以是baryon，也可以是meson，meson是由一个quark和一个antiquark组成的。既可以是定义题，也可以是简答和计算。
删除的知识点
Delete
Electric fields电场
Concept of an electric field
a) understand the concept of an electric field as an example of a field of force and define electric field strength as force per unit positive charge acting on a stationary point charge
b) represent an electric field by means of field lines
Uniform electric fields
a) recall and use E=ΔV/Δd to calculate the field strength of the uniform field between charged parallel plates in terms of potential difference and separation
b) calculate the forces on charges in uniform electric fields
c) describe the effect of a uniform electric field on the motion of charged particles
AS物理之前有对Electric field的要求，A2还会继续深入讲解关于电场的内容，2022新大纲将电场部分的内容移动到A2部分学习。
小渊说：
关于本次2022—2025新考纲A-Level物理AS部分的一些改动，到这里就结束了，小伙伴要好好学习哦!希望大家都能拿到名校offer!
