Bilingual edition: English is preserved and Chinese follows each unit. Terminology uses the confirmed v20260916 glossary; automated semantic review remains traceable.
中英双语版:英文原文完整保留,中文紧随对应单元;术语采用 v20260916 确认表,自动语义审校结果可追溯。

Some Physically Useful Definite Integrals

一些物理上有用的定积分

This is just a sampling of some of the definite integrals which appear in physical problems

这仅仅是物理问题中出现的一些定积分的示例

Application:
molecular velocity distribution

Other definite integrals associated with Gaussian distribution.
应用:分子速度分布 其他与高斯分布相关的定积分。
Squares of trig functions
三角函数的平方
Indefinite integrals
不定积分
Index
索引
 
HyperPhysics*****HyperMath*****Calculus
HyperPhysics ***** HyperMath ***** 微积分
R Nave
Go Back
返回





Definite Integrals Associated with Gaussian Distributions

与高斯分布相关的定积分

In physical systems which can be modeled by a Gaussian distribution, one sometimes needs to obtain the average or expectation value for physical quantities. If these properties depend on x, then they can be integrated to find the average value. For the first five powers of x, the integrals have the following forms:

在可以由高斯分布建模的物理系统中,有时需要计算物理量的平均值或期望值。如果这些性质依赖于x,则可以通过积分来求得平均值。对于x的前五个幂次,积分形式如下:

Applications:
应用:
Average molecular kinetic energy
平均分子动能
Index
索引
 
HyperPhysics*****HyperMath*****Calculus
HyperPhysics ***** HyperMath ***** 微积分
R Nave
Go Back
返回





Definite Integrals of the Squares of Trig Functions

三角函数平方的定积分

In dealing with sinusoidal functions associated with waves and those associated with AC electric circuits, the squares of trig functions appear. If they are averaged, then the average of the square of a trig function is found to be 1/2, so long as you are taking an integer number of quarter periods.

在处理与波相关的正弦函数以及与交流电电路相关的正弦函数时,三角函数的平方会出现。如果对它们进行平均,那么三角函数平方的平均值被发现为1/2,只要你取的是整数个四分之一周期。

Applications:
应用:
AC electric power
交流电电功率
Radiated power from surface
从表面辐射的功率
Propagated power in EM wave
电磁波中的功率传播
Index
索引
 
HyperPhysics*****HyperMath*****Calculus
HyperPhysics ***** HyperMath ***** 微积分
R Nave
Go Back
返回