Formula Definition and 1000 Threads

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.

View More On Wikipedia.org
  1. C

    How to get the structural formula of C3H6CI2?

    TL;DR Summary: I only know how to solve the C3H6 which is a double bond, is it right or wrong? Reference: https://www.physicsforums.com/forums/chemistry.83/post-thread
  2. zachary570

    Chemistry Finding the molecular formula of an unknown hydrocarbon

    Hello, I am having some trouble finishing this problem from my textbook and would like some insight on the problem. We are looking for the molecular formula of a hydrocarbon. So, if we let x = number of C atoms and y = number of H atoms then we need to find ##C_xH_y##. From the problem...
  3. H

    Help is needed for converting units of a simple formula

    How would you convert a volume mixing ratio [m3/m3] to the units of [molecules/cm3]? The temperature is given to be 293K and the air density is 1 kg/m3. Please help!
  4. Demystifier

    A Found a new formula of Dirac calculus

    I have found a new formula in Dirac calculus. The formula is elementary, so probably I'm not the first who found it. Yet, I have never seen it before. As many other formulas in Dirac calculus, it is not rigorous in the sense of functional analysis. Rather, it is a formal equality, which is only...
  5. 1

    Mastering Combinatorics: Exploring the Formula for Permutations

    My combinatorics professor has a MA, PhD from Princeton University. On our test, she asked I handwrote, but transcribed in Latex, my answer below. How can I improve this? What else should I've written? Professor awarded me merely 50%. She wrote
  6. LarryS

    Formula for Resonant Frequency of 2 Metal Coaxial Cylinders?

    Consider an LC circuit consisting of a parallel plate capacitor and a solenoid inductor in series. The formula for the resonant frequency of this circuit is 1/√(LC) where “L” is the inductance of the solenoid and “C” is the capacitance of the capacitor. Now consider a high-frequency cavity...
  7. M

    Solving kinematic formula for t

    For ## d = v_it + 0.5at^2##, can we solve for t without using the quadratic formula? Many thanks!
  8. nomadreid

    I Is this the Fourier Number, or some other formula?

    This is on a building in Korea, and the F0 made me think of the Fourier number, but the rest of the formula is unfamiliar to me. Does anyone recognize it?
  9. Shreya

    What is the derivation of the second equation for area velocity?

    I think I understand how the first equation comes about. In ##dt## the particle travels by ##dr##, I considered it as a triangle with altitude ##r## and base ##dr##. On dividing the area travelled in ##dt## by ##dt## we get the above equation. A similar argument can be applied to ##\frac 1 2...
  10. V

    I Cannot understand formula for molar heat capacities of an ideal gas

    Homework Statement:: I am trying to understand a formula given in our book for determining molar heat capacity of an ideal gas under different thermodynamic processes using a single formula, but it is confusing. The exact formula for different processes is in the screenshots below. Can someone...
  11. L

    Struggling to rearrange a formula to find c

    I am trying to get to grips with rearranging this formula to find c Vc = Vs ( 1 -e -t/rc ) i can plug the numbers in to a point but im unsure about rearranging to create the new formula
  12. N

    Weird barometric formula experiment results in Excel

    Hi, as I know the barometric formula is an exponential equation, but when I did the experiment with a barometer at different heights and inserted these results in Excel for curve fitting, it showed a weird thing, I think. So exponential equation did show that R^2=0.942 and the second-degree...
  13. C

    Formula for Xo and Yo for graph of quadratic function

    Can someone please tell me where I am wrong. I am learning how to write ##a^{2} + bx + c## in this form ##f(x)= a(X-X_0)^{2} +Y_0##. The method used in my textbook is a reduction to the perfect square. And it goes like this: ##f(x)=ax^2+bx+c## ##=a[x^2+\frac{b}{a}x]+c## ##=a\left [...
  14. ke7ijo

    B Differentiating Euler formula vs. multiplying by i

    I differentiated both sides of Euler's formula with respect to x : e^ix = sin x + i cos x => ie^ix = cos x - i sin x Then for comparison I multiplied both sides of Euler's formula by i: e^ix = sin x + i cos x => ie^ix = i sin x - cos x Each of these two procedures seems to yield the...
  15. andymag

    A Formula for force between two sheets of aluminum foil under voltage

    Hi guys, I am struggling to find the answer on Google and at forums. I am experimenting with two sheets of aluminum foil that are separated by a thin plastic foil. In theorie they should be attracted to each other if I connect one foil to power and other to ground of a DC voltage source. I am...
  16. D

    B Verifying AI Chatbot's Answer on Brachistochrone Curve Formula

    I was interviewing an AI chatbot and was wondering how good it is at physics… can anyone confirm whether the answer it gave is true or false? This was through a chatbot called ChatGPT. My prompt: What’s the formula for the Brachistochrone curve? The AI answer: The Brachistochrone curve is a...
  17. S

    Calculating Probability Using Bayes' Formula: Solving for P(urn III | silver)

    From my understanding of Bayes formula, it should look like something like this P(Silver| III) = \frac{P(III | silver) \times P(silver)}{P(III)} now we know that P(urn III) = 1/3 and the probability of P(silver) = Pr(silver|urn I) + P(silver|urn II) + P(silver|urn III) = 1/3 (0) + 1/3 (1/2)...
  18. M

    How to prove this using Abel's summation formula?

    Before I apply/use the Abel's summation formula, how should I find ## f(x) ##?
  19. Lotto

    B Can we use molecular speed of gas formula also for the air?

    Molecular speed of gas is generally $$v=\sqrt{\frac{3RT}{M}},$$where R is gas constant and M is molecular mass. Can we use this formula for the air as well, when the air is a mixture of different gasses?
  20. B

    I Find an explicit formula for this n-sum problem

    Hello, I am having trouble with deriving an explicit formula (if one exists) for S(a,n) such that for example $$S(a,5) = \sum_{i5=a}^{49} \sum_{i4=i5}^{49} \sum_{i3=i4}^{49} \sum_{i2=i3}^{49} \sum_{i1=i2}^{49}(1)$$ or $$S(a,4) = \sum_{i4=a}^{49} \sum_{i3=i4}^{49} \sum_{i2=i3}^{49}...
  21. M

    Use Euler's summation formula to prove the following....

    Proof: Let ## x\geq 2 ##. Then ## \frac{d}{dt}(\frac{ \log {t}}{t^3})=\frac{1-3\log {t}}{t^4} ##. By Euler's summation formula, we have that ## \sum_{n\leq x}\frac{ \log {n}}{n^3}=\int_{1}^{x} \frac{\log {t}}{t^3}dt+\int_{1}^{x} (t-[t])(\frac{1-3\log {t}}{t^4})dt+(x-[x])\frac{log {x}}{x^3} ##...
  22. A

    I Formula for integration of natural coordinates over an element

    In a textbook I own a formula is given for the integration of natural coordinates over an element. In this case it is a 1 dimensional element (i.e. a line segment) with coordinates ##x_i## and ##x_j##. The coordinate ##x## over the element is written as: $$ x = L_1(x) x_i + L_2(x) x_j $$ with...
  23. xiaoyaozizai

    What Formula Should I Use for Coefficient of Volume Expansion?

    I don't know what formula to use to figure that out,help
  24. SchroedingersLion

    I Integral change of variables formula confusion

    Greetings all. I just got confused by the following. Consider volume integral, for simplicity in 1D. $$ V(A) = \int_{A} dz. $$ If ##z## can be written as an invertible function of ##x##, i.e. ##z=f(x)##, we know the change of variables formula $$ V(A)=\int_{A} dz= \int_{z^{-1}(A)} |z'(x)|dx...
  25. RealityMechanics

    Determining Reverse Mass Flow Rate Formula for Multiple Diameter Tubes

    Alright, this is more of a conceptual question than a HW question that will nonetheless help me design something. In the attached image, air is flowing through a large area tube and then a small area tube from right to left. A collaborator previously figured out the equation for measuring the...
  26. StenEdeback

    Deduction of formula for Lagrangian density for a classical relativistic field

    Hi, I am reading Robert D Klauber's book "Student Friendly Quantum Field Theory" volume 1 "Basic...". On page 48, bottom line, there is a formula for the classical Lagrangian density for a free (no forces), real, scalar, relativistic field, see the attached file. I like to understand formulas...
  27. whartung

    B Applying the distance formula d= v*t + 1/2a*t^2

    On this page: https://www.physicsclassroom.com/class/1DKin/Lesson-6/Kinematic-Equations They have this for the distance traveled with acceleration formula: d= v*t + 1/2a*t^2 Now, I'm quite familiar with 1/2at^2 part, it's the v*t part that's troubling me. If I have something going 1000m/s...
  28. E

    A Higher approximations of Ramanujan formula for ##\pi##

    One of the Ramanujan formulae for π is ##(9^2+22^2/19)^{1/4}=3.14159265258##. It is precise to 9 digits. I did not read about higher approximations so that they are by the same pattern and that describe an arbitrary number of digits of π. Do these higher approximations not exist, or it is not...
  29. Dario56

    I Boltzmann Entropy Formula – Derivation

    Boltzmann entropy definition is given by: $$ S = k_B lnW $$ where ##W## is the weight of the configuration which has the maximum number of microstates. This equation is used everywhere in statistical thermodynamics and I saw it in the derivation of Gibbs entropy. However, I can't find the...
  30. X

    I Formula for Doppler effect in moving medium?

    Hi, I know the usual formula for both moving source and receiver in a static medium (from wiki): Is ir correct? What about when the medium is moving too? I can't seem to find an answer, and worst, I'm finding contradicting ones. For example, when the source and the receiver are moving at the...
  31. ContrapuntoBrowniano

    B Ideal gas formula not working?

    Hi! I wanted to do some basic calculations for temperature T on a water-filled pot. I noticed something strange on my calculations, and couldn’t figure out what was wrong... So here it is: The ideal gas formula: k=PV The actual formula Relates equally the product PV with the a constant...
  32. K

    Brain blocked on recalling this formula

    Trying to build a mixing fluid calculator and cannot for the life of me figure out how to solve for m2 rather then Tf Got an answer to question 1, but bonus question: is there anyway to solve for m2 and m1 if mt is known? IE given a total volume of mixture IE 99ml, at 20 deg. I know T1 is 25...
  33. benorin

    I Functions.wolfram.com accepted and published my formula for Gamma Fn

    I sent them an email about a week or so ago with the images of the following from the solutions to exercises section 1 of my Insight Article A Path to Fractional Integral Representations of Some Special Functions: 1.9) Use partial fraction decomposition and the Euler limit definition of the...
  34. F

    B Compound Angle Formula: Solving Double Angle Equations

    Hi, I am confused about how to handle the double angle formula. For example, sin(19pi/12)= sin(9pi/12+10pi/12) but there can be many other options too. like sin(18pi/12+pi/12) or sin(15pi/12+4pi/12)..every time I am getting different answers. Can anyone please how find the right one? Thanks
  35. mcastillo356

    B Mean-Value Theorem, Taylor's formula, and error estimation

    Hi, PF Taylor's formula provides a formula for the error in a Taylor approximation ##f(x)\approx{P_{n}(x)}## similar to that provided for linear approximation. Observe that the case ##n=0## of Taylor's formula, namely, ##f(x)=P_{0}(x)+E_{0}(x)=f(a)+\dfrac{f'(s)}{1!}(x-a)##, is just the...
  36. Y

    Milk + citric acid or pineapple juice formula? (chemistry)

    I have a chemistry project involving milk coagulation under certain circumstances. One of the circumstances is milk combined with citric acid or pineapple juice. I need to find the chemical formula of this reaction.
  37. S

    I Understanding the Clausius-Clapeyron Formula: V_{l} and V_{g}

    Hey, I have a question about the meaning of a variable in the Clausius-Clapeyron formula. My textbook (Daniel v. Schroeder) says that the Clausius-Clapeyron formula is (for phase boundary between liquid and gas) \frac{dP}{dT} = \frac{L}{T\left(V_{g} - V_{l} \right)} . What is V_{l} or V_{g}...
  38. bluesteels

    AC circuit power formula question

    im kinda confused on why can't you just use the formula P=I^2R. Can you just use Vrms or Vamp (not sure which one is it) and the value of R which is 105Ω to solve for I Then just plug it in the formula P=I^2R. But when i did that it the wrong answer so is this formula don't work for AC...
  39. A

    MHB Formula to find arc radius using arc length, chord length, and/or segment angle

    I'm attempting to write some code using the Ruby programming language that will give me the radius of an arc but the only pieces of information I have to work with are the arc length (L), the chord length (C), and the circular segment angle in degrees (A): I'm hoping someone can show me how to...
  40. P

    I Compressed gas energy storage formula

    Hi, I’m looking for formula to find the energy stored in a compressed gas for non ideal gases, for example, argon. The formula should also include the thermal energy caused by compression. Thank you in advance.
  41. benagastov

    Spectral Intensity Formula by Using Frequency

    I found there is kind of solution in Pointon's book: An Introduction to Statistical Physics for Students. But I don't know how to find intensity by using frequency.
  42. T

    I Finding a general formula for a recursive sequence

    The general formula for the nth term of the Fibonacci sequence where an=an-1+an-2 can determined by matrix diagonalizations Is there a way to determine the formula of any recursive sequence say an=a1+a2+...an-1
  43. M

    I Formula for redshift of photon decoupling

    I have come across an old formula from my notes and I have no reference for it but it is using truncated digits in its formula to calculate the redshift for decoupling. The formula is nearly as accurate as the observed data from Planck 2018. So I would like to figure out the derivation of those...
  44. DaveC426913

    Open Office Calc (Ersatz Excel) formula

    I want a column that displays what standing each team has. (I can't really Google a solution because I don't even know what to call it.) This the idea: - team 1 is "1st", - teams 3 and 10 are "2nd", - team 5 is 3rd, etc.: I can't think of a way of doing it that isn't very complex...
  45. elElegido

    A misconception I have about impulse formula interpretation

    The misconception came up from the following problem: "A 0.50-kg cart (#1) is pulled with a 1.0-N force for 1 second; another 0.50 kg cart (#2) is pulled with a 2.0 N-force for 0.50 seconds. Which cart (#1 or #2) has the greatest acceleration? " I know the answer is the following (I looked it...
  46. bluesteels

    Power formula for circuit when another resistor is added in

    On Chegg they solve for V using P=V^2/R using 36W and R1= 25Ω, which is equal to 30V then they add R1+R2 = 40Ω and they plug in P=V^2/R and solve for P which is 22.5W I'm confused on why they didn't use P=I^2*R cause you know the system is in series so I is the same and solve for I then...
  47. Salmone

    A Prove a formula with Dirac Delta

    Why is the Laplacian of ##1/r## in spherical coordinates proportional to Dirac's Delta, namely: ##\left(\frac{\partial^2 }{\partial r^2}+\frac{2}{r}\frac{\partial }{\partial r}\right)\left(\frac{1}{r}\right)=-\frac{\delta(r)}{r^2}## I get that the result is zero.
  48. diazdaiz

    B Help Me Determine Validity of Time Dilation Formula

    I recently trying to learn General Relativity by first scraping the surface on ScienceClic's general relativity playlist, and then I stumbled upon a video where it said that we actually move through spacetime on a constant speed of c, and then I remember about time dilation because how speed on...
  49. mcastillo356

    Edit: how to colour an edited formula

    Hi PF How to colour the edited formula? Greetings!
  50. A

    I The probability density function for the double-slit experiment

    I am desperate. I've scoured the web for the formula for the probability density function for the interference pattern obtained in the double slit experiment with both slits open. So I want to know the probability density function and not the intensity function. I prefer not to have references...
Back
Top