In science, a formula is a concise way of expressing information symbolically, as in a mathematical formula or a chemical formula. The informal use of the term formula in science refers to the general construct of a relationship between given quantities.
The plural of formula can be either formulas (from the most common English plural noun form) or, under the influence of scientific Latin, formulae (from the original Latin).In mathematics, a formula generally refers to an identity which equates one mathematical expression to another, with the most important ones being mathematical theorems. Syntactically, a formula(often referred to as a well-formed formula) is an entity which is constructed using the symbols and formation rules of a given logical language. For example, determining the volume of a sphere requires a significant amount of integral calculus or its geometrical analogue, the method of exhaustion. However, having done this once in terms of some parameter (the radius for example), mathematicians have produced a formula to describe the volume of a sphere in terms of its radius:
V
=
4
3
π
r
3
{\displaystyle V={\frac {4}{3}}\pi r^{3}}
.Having obtained this result, the volume of any sphere can be computed as long as its radius is known. Here, notice that the volume V and the radius r are expressed as single letters instead of words or phrases. This convention, while less important in a relatively simple formula, means that mathematicians can more quickly manipulate formulas which are larger and more complex. Mathematical formulas are often algebraic, analytical or in closed form.In modern chemistry, a chemical formula is a way of expressing information about the proportions of atoms that constitute a particular chemical compound, using a single line of chemical element symbols, numbers, and sometimes other symbols, such as parentheses, brackets, and plus (+) and minus (−) signs. For example, H2O is the chemical formula for water, specifying that each molecule consists of two hydrogen (H) atoms and one oxygen (O) atom. Similarly, O−3 denotes an ozone molecule consisting of three oxygen atoms and a net negative charge.
In a general context, formulas are a manifestation of mathematical model to real world phenomena, and as such can be used to provide solution (or approximated solution) to real world problems, with some being more general than others. For example, the formula
F = mais an expression of Newton's second law, and is applicable to a wide range of physical situations. Other formulas, such as the use of the equation of a sine curve to model the movement of the tides in a bay, may be created to solve a particular problem. In all cases, however, formulas form the basis for calculations.
Expressions are distinct from formulas in that they cannot contain an equals sign (=). Expressions can be liken to phrases the same way formulas can be liken to grammatical sentences.
http://math.sfsu.edu/federico/Clase/Math350.S15/linea.JPG 1. Homework Statement
The picture below represents the map from a "green projective line" to a "red projective line." It takes the "green points" 1,3,7,-11 to the "red points" 0,6,10,20, respectively as shown by the ruler. Let f be the...
I am trying to find a formula to determine effort to raise a ladder based on the angle of the ladder at a given time. I am concerned mostly about the angle so I can plug in an individuals height and distance toward the fulcrum. I am assuming the ladder will not slide at the footing. I included a...
I'm trying to derive a formula for the magnetic torque on a semicircular loop.
what I've done so far is this
The magnetic force on the non-curved loop is
$\vec{F}_{x}=\int Idx\hat{i}\times B_{\circ}\hat{i}=0N$
for the curved loop
$\vec{F}_{c}=\int_{0}^{\pi} Ird\phi\hat{\phi}\times...
I've been using euler's formula now more than I have in the past, (using it for circuit analysis stuff), and so its been floating around in my head a bit more.
Say you have e^{2πi}=1 and you take the natural log of both sides.
\log_e( e^{2πi})=\log_e(1)
2πi=0
uhhhhh... :confused:
Hey guys and gals, I'm taking an online physics course just to kind of learn the basics before I take the real thing this summer. The course is from OpenYale for those interested (oyc.yale.edu). Anyways, the professor was talking about some formulas for finding ##\vec{r}(t) = r(i(cos\omega t) +...
Hey! :o
Let $f: [0, \pi]\rightarrow \mathbb{R}$ a $C^{\infty}$ function for which the following stands:
$$g(0)=0 \ \ , \ \ g(\pi)=0$$
I have to show that $$\int_0^{\pi}g^2(x)dx \leq \int_0^{\pi}(g'(x))^2dx$$ using Parseval's formula.
I have done the following:
The Fourier series of $g$...
Homework Statement
log39x4 - log3(3x)2
The answer sheet says that the answer is 0, but when I work the problem both ways I get:
2log3x
Any ideas?
Homework Equations
logxy/z = logxy - logxz
The Attempt at a Solution
Formula Sheet
20-30 Minutes of Messing around with the problem
Homework Statement
I have the total energy of a hydrogen atom E and need to take the average. The uncertainty in deltax=r so the uncertainty in deltap=hbar/2r The average values of x^2 and p^2 can be identified with the squares of the corresponding uncertainties, and the constant value of E is...
< Mentor Note -- thread moved to HH from the technical math forums, so no HH Template is shown >
So the original problem was that a stationary hydrogen atom changed states from excited to lower state and emitted a photon, i solved for the energy of the photon hf taking into account the kinetic...
I was just trying for the ninetieth time to try and understand the sort of physicality Euler's formula and the role i plays in the way so many equations work - it's always been such an obstacle to reading so many of them. I mean what the heck is that i doing there. Progress, maybe, but... no...
Hey guys,
I have made an attempt at rearranging the formula below and I am looking for someone to just have a look over it and see if I got it right?Really appreciate any pointers or tips
Thank you! :-)
My observation is to verify self inductance formula by measuring the resonant frequencies of different coils in an LC circuit.For this, I am asked to use this formula by my mentor :
L = 1/(4π^2 . f^2 . C)
Here,
f = different resonant frequencies,
C = capacitance of the capacitor in the LC...
I am studying National 5 physics, and my exam is tomorrow. I need some last-minute help.
I'm struggling a little bit with the combined gas law, P1V1/T1 = P2V2/T2, and I'm not sure why.
It would help me a lot if you could show step-by-step how the formula is used.
Thanks for your time, it's very...
Since the pressure a sphere exerts on a surface tends to infinity, how do you actually calculate it? My guess would be trying to see how many atoms of the surface (a straight line) and of the sphere collide. But this is very dependent on the materials and exterior factors.
I have searched...
Dear Readers,
It has been many (30+) years since I have had to work this kind of math and it is kickin' my butt. So, if you can help a software weenie with a need for a conversion formula for ENU to ECEF (or at least an explanation of things more elementary than what I have found thus far) it...
Homework Statement
In my textbook it's written that turnbull's blue is:
## Fe_3^{II}[Fe^{III}(CN)_6]##
Homework Equations
none.
The Attempt at a Solution
But Shouldn't it be twice of the complex compound instead of one...to balance the charge.
I googled it but found the formula of the...
Use Gauss Chebyshev formula with $n=3$ to approximate the value of the integral.
$$\int \frac{x^4}{\sqrt{1-x^2}}dx$$ from -1 to 1.
Also compare the result with true value, where the zeros and the corresponding weights of the following simple set of orthogonal polynomial is given as below...
What's the chemical formula of bornite?According to wikipedia
http://en.wikipedia.org/wiki/Bornite
it is Cu5FeS4.According to http://www.spiritofisis.org/knowledge/crystal_files/bornite.htm
it is Cu2FeS4 and as per my textbook it is Cu3FeS2.Now,What's the actual chemical formula of bornite?I...
Homework Statement
The question is says:
Two vessels divided by a partition contain 1 mol of N2 and 2 mol of O2 gas. If the partition is removed and gases ate mixed isothermally, then find the change in entropy due to mixing assuming initial and final pressure are same .
Homework Equations...
I've been studying em induction and in my book it was explained by considering a metal rod of length l moving through a magnetic field and cutting through the field lines at a constant speed. So in time dt it moves through ds and they showed e=BA/dt, where A = l x ds(the area that the rod...
Homework Statement
Which formula could be correct for the speed v of ocean waves in terms of the density ρ of sea-water, the acceleration of free fall g, the depth h of the ocean and the wavelength λ?
The possible answers listed are:
1. v = \sqrt{gλ}
2. v = \sqrt{g/h}
3. v = \sqrt{ρgh}
4.v =...
Hi all,
I have a question concerning the derivative of the formula of the number of nuclei. I hope I've posted this in the right section, I'm new here :P. Anyway, in the question, the given values are:
At a certain time t, there is an amount of radioactive Br-82. The activity A is 7.4*1014 Bq...
Homework Statement
(a) What processes changes atomic number by 1? What are the favourable conditions? How do you tell a neutrino is involved? How can we use this to understand the mass of this particle?
(b) Use semi empirical mass formula to explain why odd-odd isobars are unlikely, while...
Sorry to bring this question up again.
@aridno provides a nice formula of the moment of inertia I about the centroid in https://www.physicsforums.com/threads/calculating-polygon-inertia.25293/ as:
$$...
I'm really happy about every hint!
Homework Statement
There is a ball on hight h which is dropped on a table.
With every Impact the ball loses velocity v by a factor a<1.
I Need to Show the following:
The time T after the ball stopps bouncing is:
T = \frac{1+a}{1-a} (\frac{2h}{g})^\frac{1}{2}...
I am using the following formula to determine the lb load against the bottom of a load cell from tightening the bottom anchor bolt nut (which anchor bolt goes through the center of the load cell structure and anchors to a bottom base plate) to a certain torque force, plus adding a live static...
Derive an exact formula (solve the recurrence definition) for the following recursive sequence: $s_n = 2_{s_n-1} - s_{n-2}$ where $n \ge 2$, and $s_0 = 4$, $s_1 = 1$.
So I saw someone solving this by making it a differential equation or something?
How would you do that? should I do
let...
The first moment divided by the total mass is the center of mass. Now I know that a moment is a combination of a physical quantity and distance. So what is the First moment made up of? I know that moment of inertia is made up of mass times the radius (distance) squared.
Okay so the name may be bigging it up however i found something in my maths class today that i don't think has previously been published or at least I've never been taught it, it makes converting reacuring decemals a lot quicker
I know about the over 9 rule however acording to my maths teacher...
Here's the source:http://web.mit.edu/dvp/www/Work/8.06/dvp-8.06-paper.pdf
Regarding page 5 of 14, I don't understand the multiple integrals thing. What is that supposed to mean? Ain't we supposed to sum up all the paths but why do they do the multiple integral thing?
Also regarding page 4 of...
From Apostol's Calculus Volume I, "Area as a Set Function"
1. Homework Statement :
Right triangular regions are measurable because they are constructed from the intersection of two rectangles. Prove that all triangular regions are measurable and have an area of the product of one-half, their...
Homework Statement
Using semi empirical mass formula calculate which isotope of oxygen (##_8O##) decays into mirror nuclei. Is it ##\beta +## or ##\beta -##?
Homework Equations
$$W(A,Z)=w_0A-w_1A^{2/3}-w_2\frac{Z^2}{A^{1/3}}-w_3\frac{(A-2Z)^2}{A}-w_4A^{-3/4}\delta(A,Z)$$ where $$w_0=15.8MeV$$...
While teaching momentum, we use the formula p=mv.
Every year it comes up as to why the letter p is used in the formula and not other letters or symbols. I have conducted on-line searches and I stumble across explanations that mention Newton and his Principia along with other possible...
I have a problem I am trying to solve but no example provided can clarify the steps. I find this to be the problem with math examples, they provide problems but utilize same numbers so people who are not as math savvy such as I cannot figure the steps out as easily as they are provided. Anyway...
Homework Statement
Show that both sides of the Stoke's Theorem formula are valid for the function F= using the triangular surface on the y-z plane with corners at the origin, (0,2,0) and (0,0,2).
Homework Equations
Stokes Theorem equation( not sure how to write it out here) [/B]
The Attempt...
Using R = ρL/A,
I am trying to get this formula, which is the change in resistance due to change in length, area, and resistivity.
ΔR = (∂R/∂L)ΔL + (∂R/∂A)ΔA + (∂R/∂ρ)Δρ
I understand the above conceptually, but I am confused about why we are multiplying by terms ΔL, ΔA, and Δρ.
Intuitively, I...
Hi all,
I need help finding a formula to find the volume of a solid that has a fixed width and depth but 4 different heights. To see what I mean, please take a look at a sketch I drew below.
Thanks.
When the learning combination formula the formula nCr is usually derived using a deck of cards. There are n=52 different card. If you choose r number of cards, each is different so you basically start with n!/(n-r)! , then because the order is unimportant multiply by 1/r!. This explanation is...
I tinker with single cylinder 4-stroke (kart) racing engines a good deal. Flywheel design for optimum weight has always amazed me. Does anyone have formulas for optimizing the design? It's more than just saying "x" pounds is best, because the actual shape of the flywheel, width and thickness of...
hi all..
how to make formula for problem below :
The average math test scores of 36 students is 86. There are four students attend subsequent replications and obtain an average value of 80. Find the average value of all the students!
can you make simple?
zidan3311
Hi there,
Just wondering if anyone here can help me with a real life math problem I have on my hands right now!
I am going to borrow \$48,000 from a bank as an unsecured personal loan for a 3 year period.
I have to make minimum monthly payments of 1% of the outstanding loan balance at the end...
Homework Statement
Determine the input resistance using blackmans impedance formula.
I know all the ressisor values, and transistor data.
Homework Equations
[/B]
Blackmans impedance formula
The Attempt at a Solution
Our teacher has given us a example on how to find the open loop gain, but...
Hey guys,
The following formula is provided on the wikipedia page for downforce,
D=0.5(WS)*H*alpha*F*rho*V^2
Where:
D is downforce in Newtons
WS is wingspan in metres
H is height in metres
\alpha is angle of attack
F is lift coefficient
rho, ρ, is air density in kg/m³
V is velocity in m/s...
There are n birds which need to be put back in a cage.
In a specific 10 minute period each bird will be put back at some random point in time.
Find a formula for the probability that m animals from n are put back at the same time, where the 'same time' means in the same 1 second interval...
Hey,
Could anyone explain why Ia/Ib=2.512^(Mb-Ma), Where "Ia" and "Ib" are intensities of star a and star b and "Mb" and "Ma" are the apparent magnitudes of star A and star B?
I thought the formula would be Ia/Ib=(2.512)^(Ma-Mb) because Ia=2.512^Ma and Ib=2.512^Mb.
Thank You
I'm a little confused as to how to figure out the pressure exerted on a material pressed between two solid "press plates" Let's say we have 2 .5" thick x 12" x 24" hardened steel plates. I have a 1" thick layer of cloth (say 50+ layers) of 8" x 18" (1ft^2).
The fabric is placed between the...
In the winters, I run on an indoor track, and use a footpod to calculate my distances with my GPS watch.
The facility has three lanes, inside #1 is 181.6 meters, middle lane #2 is 187.2 and outside #3 lane is 194.3 meters long. The track is more less rectangular shaped as opposed to a circle...