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Differential Equations
A differential equation, unlike other mathematical equations, has one or more of its unknowns undergoing a continual change. These equations mathematically describe the most significant phenomena in the universe, including Newtonian and quantum mechanics, waves and oscillators, biological growth and decay, heat, economics, and general relativity. Please direct all concerns about these intricate and all-encompassing equations here.
523 Questions
How can two boxes have the same volume but different surface area?
if volume = 1, the following(and an infinite number more possibilities) can be true:
1. length=1
width=1
height=1
2. length=.5
width=.5
height=4
3. length=.1
width=5
height=2
....
all have the same volume but different Surface area
How is a blast radius calculated?
See the book The Effects of Nuclear Weapons for equations. My copy came with a circular slide rule that calculates that for optimal altitude airburst and surface burst over a yield range of 1 KTon to 10 MTon. It also calculates many other effects.
What is 2kn per sq meters in kg?
A kn per sq metre is a measure of pressure and has units [ML-1T-2] whereas a kilogram is a measure of mass and has units [M]. The two measure different things and, according to basic principles of dimensional analysis, any attempt at conversion from one to the other is fundamentally flawed.
What job can you get making eighty five thousand dollars a year with out going to college?
Sales. Autoglass chip repair but you must be self employed. Not hard to learn, or a hard buissiness to run. See I can't even spell rite and I'm doing it.
What is cauchy riemen equation?
partial of u with respect to x = partial of v with respect to y
partial of u with respect to y = -1*partial of v with respect to x
A Bessel function is any of a class of functions which are solutions to a particular form of differential equation and are typically used to describe waves in a cylindrically symmetric system.
How do you derive Poisson's equation from Maxwell's equations?
Start with the differential form of Gauss's law:
∇ â— E = Ï/ε0, the divergence of the electric field is equal to the total charge density divided by the permittivity of free space.
Make the following substitution, assuming electrostatic charges:
E = -∇φ, the electric field at a point is equal to the negative gradient of the scalar electric potential.
This gives:
∇ ◠∇φ = -Ï/ε0
From an identity of vector calculus we get the following:
∇2φ = -Ï/ε0, which is Poisson's equation with f = -Ï/ε0.
What is the general equation of heat loss?
If you're looking for an equation that describes the loss of heat of an object in terms of time and the ambient temperature I would recommend Newton's law of cooling.
Look for it here http://www.ugrad.math.ubc.ca/coursedoc/math100/notes/diffeqs/cool.html
9.6 = 48/5 as an improper fraction in its lowest terms
