Nature, in the broadest sense, is the natural, physical, material world or universe. "Nature" can refer to the phenomena of the physical world, and also to life in general. The study of nature is a large, if not the only, part of science. Although humans are part of nature, human activity is often understood as a separate category from other natural phenomena.The word nature is borrowed from the Old French nature and is derived from the Latin word natura, or "essential qualities, innate disposition", and in ancient times, literally meant "birth". In ancient philosophy, natura is mostly used as the Latin translation of the Greek word physis (φύσις), which originally related to the intrinsic characteristics that plants, animals, and other features of the world develop of their own accord.
The concept of nature as a whole, the physical universe, is one of several expansions of the original notion; it began with certain core applications of the word φύσις by pre-Socratic philosophers (though this word had a dynamic dimension then, especially for Heraclitus), and has steadily gained currency ever since. During the advent of modern scientific method in the last several centuries, nature became the passive reality, organized and moved by divine laws. With the Industrial revolution, nature increasingly became seen as the part of reality deprived from intentional intervention: it was hence considered as sacred by some traditions (Rousseau, American transcendentalism) or a mere decorum for divine providence or human history (Hegel, Marx). However, a vitalist vision of nature, closer to the presocratic one, got reborn at the same time, especially after Charles Darwin.Within the various uses of the word today, "nature" often refers to geology and wildlife. Nature can refer to the general realm of living plants and animals, and in some cases to the processes associated with inanimate objects—the way that particular types of things exist and change of their own accord, such as the weather and geology of the Earth. It is often taken to mean the "natural environment" or wilderness—wild animals, rocks, forest, and in general those things that have not been substantially altered by human intervention, or which persist despite human intervention. For example, manufactured objects and human interaction generally are not considered part of nature, unless qualified as, for example, "human nature" or "the whole of nature". This more traditional concept of natural things that can still be found today implies a distinction between the natural and the artificial, with the artificial being understood as that which has been brought into being by a human consciousness or a human mind. Depending on the particular context, the term "natural" might also be distinguished from the unnatural or the supernatural.
By using the term "common ethics" I am referring somewhat to the idea of "common sense". You see it everyday in traffic, among pedestrians, in classrooms and everywhere there is human activity. We could say you can find it in the animal and plant kingdoms as well, but that would be an outright...
hello,
I was trying to figure out what will be the y value for this equations:
1 - e^-0.15*10^-5*y = 0.1
Could somebody help me in this?? The answer is supposed to be 70,240.
thanks.
Hi
Natural frequency of spring is fn = 1/(2*pi) * sqrt(k/m), where k = spring constant and m is the mass.
Ok, so I have a spiral spring which means that spring is coiled couple of times. Its spring constant is (according to Hartog's Mech. Vibrations), k = E*I/l, E=Elastic Modulus, I = Inertia...
Homework Statement
A Consistency question regarding the dimensions of the KG Equation.
Homework Equations
M^2=\frac{\hbar c}{G} for a quantization of gravitational charge on matter
The Attempt at a Solution
I know a few things however concerning the KG equation. It is directly...
Homework Statement
If 6 J of work is needed to stretch a spring from 10 cm to 12 cm, and another 10 J is needed to stretch it from 10 to 12 cm, what is the natural length of the spring?
Homework Equations
W=FD
Hooke's Law
The Attempt at a Solution
Honestly, I stare at this problem...
Hello,
I'm thinking about a natural convection problem where you have turbulent flow on a vertical wall. It's compressible flow, and it's a two-phase problem. You have two boundary layers, one for the air-vapor mixture, and one for the condensate.
The question I'm pondering is this...
HI
when dealing with natural convection, we use grashof's number. suppose we have a heated plate of temperature Tp. and heat being transferred to surrounding air by convection, air of temp Ta.
So film temp is Tf = 0.5(Tp + Ta)
If grashofs numbers, Gr = \frac { \beta gL^3 \delta...
Homework Statement
Show that for any natural number K, there is an n large enough so that (2^n) > K.
Homework Equations
The Attempt at a Solution
K is a natural number -> the smallest possible K would be 0 (lower bound?) and the smallest 2^n is 1 when n = 0, and the upper bound...
Hi guys, I need to find the natural frequencies of a series of pressure rakes. We have a numerical model, but I'd like to confirm with a hand calculation. I would like to model the pressure rakes as a cantilevered beam with varying cross section (i.e. as each tube "stops" the beam decreases in...
Hey all, I'm really having a hard time figuring out a couple of problems in which I have to differentiate:
1: \frac{e^3^x}{\ln x}
I just don't know how to put it together... I know that e^3^x is 3e^3^x, and I know that you can't different \ln x, so I don't know what to do from there...
I would like to calculate the natural frequency of a cantilevered spiral coil. So instead of having a standard beam which is straight, I have a beam which has one end fixed to an axle and the beam is spiralled several times around the axle. The end of the beam comes out of the spiral and runs...
Homework Statement
Hi all, I'm having an issue with a homework problem. I'm taking a vibrations class and in our lab we had a cantilever beam with a mass on the end. There is an accelerometer on the beam and we used an impulse hammer to hit the beam. We had software that recorded all the...
I have to prove that for all k,m,n \in N that if m+k = n+k, then m=n.
The problem mentions that I must prove this by induction.
I did the base case k = 0: If m+0 = n+0, by identity m=n.
Then I attempt to show that m+1 = n+1 implies m=n, but I am stuck, I don't see how induction can be...
ln(x+1) + ln(x+3) < ln(x+7)
Find x!
I should of course know this, second year at high school (in Norway). I've just forgotten the way attack the whole thing^^
Homework Statement
\displaystyle\int\left(\dfrac{\ln x}{x}\right)^2 dx
2. The attempt at a solution
I tried letting u=\ln^2 x and dv the rest and I also tried dv=\ln^2 x dx and u the rest. It won't work out.
This is perhaps a stupid question but:
When we use natural units and set h=c=1, do we choose appropriate units so that their value is one but these constants still have dimensions, or are we somehow choosing h=c=1 to be a pure number with no dimensions?
Homework Statement
Let a,b \inR with a < b. and let n \inN where n(b-a) > 1.
a) How do you know that such an n must exist?
b) Show that there exists m \inZ where a < m/n < b
c) Show that there exists some irrational c where a < c < b (Hint:rational + irrational = irrational.)
Homework...
I'm certain this is a silly question but: Do photosynthetic plants require natural sunlight to undergo photosynthesis, or will artificial light from flourescent lights suffice?
Thanks!
Homework Statement
Hi.
I want to solve:
\frac{d\ln(-x)}{dx}.
When using the chain rule I get:
\frac{d \ln(-x)}{dx} = \frac{d\ln(-x)}{d(-x)}\frac{d(-x)}{dx} = -\frac{d\ln(-x)}{d(-x)}.
But how do I find the last derivative? I know by experience that it is -x-1, but how is the derivation...
Hi,
I'm a 2nd semester student in the Indian Institute of Technology, Kanpur. My fields of interest are AI, particularly machine learning, pattern recognition etc. I have done a project on pattern recognition in the Indian Statistical Institute, Kolkata.
I've some ideas about constructing...
Dear PF members,
In terms of natural units the reduced Planck's constant (\hbar) is 1 ML2T-1. Now in this terminology how a magnetic field can be expressed?
thanks for your reply,
rajini
If n is a natural number then n2+n+3 is odd.
This is what I have and wanted to know if I was doing it right or not:
Let n be a member of the natural numbers. If n is even, then n=2k, k member of natural numbers, and n2+n+3
=(2k)2+2k+3
=4k2+2k+3...
Homework Statement
How would I begin to integrate ln(t+1) from 0 to e^2x?
Homework Equations
d/dx[log base a of u]=1/(lna)u du/dx
Can the original equation be manipulated to use this derivative?
The Attempt at a Solution
Not sure where to start.
Pardon me for my ignorance -- and naivety, if this question idicates it -- but would it be possible to change the rotation of a planet or moon? We'll assume the hypothetical people attempting this project have a nearly infinite budget, but even with quadrillions of dollars, is this even...
Homework Statement
Find the inverse equation (i.e. solve for x)
y=(e^x)/(1+2e^x)2. The attempt at a solution
e^x = y(1+2e^x)
x = ln(y) + ln(1+2e^x)
?
Profit!
I can't figure out what to do with ln(1+2e^x) to get the x out of there so I can finish isolating x. I tried balancing it another way...
The text I'm reading explains how there is a natural isomorphism between a vector space and the dual of the dual of the vector space. The author explains that this is so because the isomorphism he defines makes no reference to a specific basis of the vector space. I understand that natural...
Introduction
Hello, I have some problems proving the following problem: "AvB |- BvA". I would like to prove this by using natural deduction only. (I know it is possible proving it using truth tables).
Syntaxis
To avoid confusion I will use the following syntaxis to show my problem...
Well, similair to the reasons behind gravity as in theory of relativity, i would like to know the reasons behind electro magnetism. i would also like to know how exactly the strong force holds hardons toghether and produces atomic stability in varying spaces. Also, why and how is the strong...
What expression should be used to calculate Nusselt number for free convection (of air) in a vertical channel with walls at different temperatures?
I have the Bar-Cohen and Rohsenow equations, but I am unsure which situation this corresponds to (and thus which constants to use).
Symmetric...
What gives rise to natural frequency? Resonance is when an oscillating force has a frequency that matches the natural frequency of a system... but what gives rise to the natural frequency of the system?
Hi.. I have a question about natural fvibration.
Every object has natural frequency and modes of vibration.
Let us consider a simple cantilever beam for our discussion.
and Let's say its first 4 modes of vibration are at 3, 6, 10 and 20 kHz respectively.
(I made up these frequency values)...
I just watched some pbs program about the universe, and the conclusion was that existence is no accident, its the universe working for billions of years... seriously? you just wasted 1hr of my time to tell me something a little kid couldve told me in 10secs..?
Im no scientist... but i can...
As a CO2-global warming denier (GWD), how nuclear power generation compare to natural gas and oil carbon fuels, in start up costs, long term costs, pollution, operating costs?
Is there any reason natural gas and oil fossil fuels can not meet projected energy needs, besides the allegation of...
Hey all. I'm having some problems with the partial derivatives of e. I understand the basics such as exy2. where I'm getting confused is with the following
dz/dx=e(x+y)
and
dz/dx=1/ex+ey
Can anyone help me out with understanding these??
In How many ways can one write a natural number M as a sum of N whole numbers?
Consider the two conditions;
1)the numbers appearing in the sum are distinct.
2)the numbers appearing in the sum are not necessary distinct.
eg1:eight can be written as a sum of 6 whole numbers as shown below...
If someone dies in a hospital a member of medical staff tries to brings their heart back to life, sometimes this works. Why if someone dies of nateral causes can't their heart be braught back to life after a while?
1.
I was trying to understand the proof of
(d/dx) b^x = (ln b)*(b^x)
it says:
b= e^(ln b)
so, b^x= e^((ln b)*x))
So now we use the chain rule:
(d/dx) b^x = (d/dx) e^((ln b)*x))
I understand everything so far, but not the next step.
It says then that
(d/dx) e^((ln b)*x))= (ln...
Homework Statement
The portion of a piano string between the bridge and upper end of the finger board is 0.50 meters long. The string when plucked sounds a note of 440Hz- the first harmonic.
a. where must the violinist put a finder to pay a C note- 528Hz
b Without returning, is it possible...
I encountered a proof problem when I was reading up on the derivatives of natural logarithms' section. It gave a rule which said this : \text{For } a >0 \text{ and } a\ne 1 \text{,}\\\frac{d}{dx}(a^{u}) \ = \ a^{u} \ \ln{a\frac{du}{dx}}
To prove it on my own, I made a few identities:
a^{u}=y...
Homework Statement
We're doing a lab and we basically had to find ln(Pv), where Pv is vapor pressure of isopropanol. Well, the pressure is initially measured in kPa, but what happens to the units if you take a natural log of that whole thing?
For example, if I take ln(5 kPa), do the units...
Integrating Natural Log Function using "Integration by Parts" Method
Homework Statement
The problem says to integrate ln(2x+1)dx
Homework Equations
I used u=ln(2x+1); du = 2dx/(2x+1); dv=dx; v=x
The Attempt at a Solution
So, I integrated it using that (above) 'dictionary' and I...
I'm watching a show about reintroducing bison to the great plains, because man killed most of them off. In the same breath they talk about how indians would burn the plains to attact bison to the new growth and that's why there were so many of them. Who decides which is the natural order? I'm...
Homework Statement
F(x) = (8-12ln|x|)/(x^4) > 0
(a) For what values of x is the expression F(x) defined?
Write your answer in interval notation.
(b) At what value(s) of x is the expression F(x) equal to zero?
If there is more than one answer separate them by commas.
(c) The set of...
I don't know if this is more appropriate for the topology forum, but I am learning this in analysis. I am asked to say whether or not Q and N are homeomorphic to each other and to justify why. I am confused as to how to prove precisely that two spaces are homeomorphic, for there are no formal...
Homework Statement
A 950kg sports car (including driver) crosses the rounded top of a hill (radius = 86.0m) at 10.0m/s.
Homework Equations
A. Determine the normal force exerted by the road on the car.
B. Determine the normal force exerted by the car on the 73.0kg driver.
C. Determine the car...