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The Clausius-Clapeyron relation describes the relationship between pressure and temperature for a substance at a phase transition, such as liquid and vapor. For water vapor, it shows that saturation vapor pressure increases exponentially with temperature. The approximate form is [latex]\frac{dp}{dT} = \frac{L}{T(V_v - V_l)} \approx \frac{L p}{R_v T^2}[/latex], where L is latent heat.

涡流是根据法拉第定律，由变化的磁场在块体导体内感应出的电流环。它们在垂直于磁场的平面内以闭合环路流动。根据楞次定律，这些电流会产生自身的磁场，抵抗外部磁通量的变化，从而产生排斥力或阻力以及电阻加热。

铅酸电池是第一种可充电电池，由加斯顿·普兰特于1859年发明。它使用浸入硫酸（H₂SO₄）电解液中的铅（Pb）阳极和二氧化铅（PbO₂）阴极来工作。放电时，两个电极都会转化为硫酸铅（PbSO₄），充电时则发生逆转，从而实现能量的储存和重复利用。

This is the differential form of Faraday's law of induction, one of Maxwell's four equations. It states that a time-varying magnetic field ([latex]\mathbf{B}[/latex]) always accompanies a spatially varying, non-conservative electric field ([latex]\mathbf{E}[/latex]). The relationship is expressed as [latex]\nabla \times \mathbf{E} = -\frac{\partial \mathbf{B}}{\partial t}[/latex]. This equation governs how changing magnetic fields create electric fields at a specific point in space.

麦克斯韦方程组是一组由四个耦合偏微分方程组成的方程组，构成了经典电磁学的基础。它们描述了电场和磁场如何相互产生，以及它们如何被电荷和电流改变。它们是高斯​​定律、高斯磁定律、法拉第电磁感应定律和安培-麦克斯韦定律。

焦耳-汤姆逊（或焦耳-开尔文）效应描述的是实际气体在保持绝缘的情况下，被迫通过阀门或多孔塞（即等焓过程）时的温度变化。在给定压力下，气体具有反转温度。如果气体膨胀至低于该温度，则会冷却；如果气体膨胀至高于该温度，则会升温。这种冷却效应是现代制冷和液化技术的基石。

首款商业化成功的可充电电池。它采用铅 (Pb) 阳极、二氧化铅 (PbO₂) 阴极和硫酸 (H₂SO₄) 电解质。放电过程中，两个电极均转化为硫酸铅 (PbSO₄)，并消耗硫酸。该过程可通过施加外部电流实现化学可逆，使其成为一种实用且可靠的储能系统。

One of the four Maxwell's equations, Gauss's law for magnetism states that the net magnetic flux out of any closed surface is zero. This is expressed mathematically as [latex]\oint_S \vec{B} \cdot d\vec{A} = 0[/latex]. This law is a statement of the experimental observation that magnetic monopoles (isolated north or south poles) have never been detected. Magnetic field lines always form closed loops.

Electromagnetic waves are disturbances of the electromagnetic field that propagate through space, carrying energy. They are created by accelerating electric charges and consist of synchronized, perpendicular oscillations of electric and magnetic fields. In a vacuum, they travel at the speed of light, [latex]c[/latex]. The electromagnetic spectrum encompasses radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays.