A calculation is a deliberate process that transforms one or more inputs into one or more results. The term is used in a variety of senses, from the very definite arithmetical calculation of using an algorithm, to the vague heuristics of calculating a strategy in a competition, or calculating the chance of a successful relationship between two people.
For example, multiplying 7 by 6 is a simple algorithmic calculation. Estimating the fair price for financial instruments using the Black–Scholes model is a more complex algorithmic calculation.
Statistical estimations of the likely election results from opinion polls also involve algorithmic calculations, but produces ranges of possibilities rather than exact answers.
To calculate means to determine mathematically in the case of a number or amount, or in the case of an abstract problem to deduce the answer using logic, reason or common sense. The English word derives from the Latin calculus, which originally meant a small stone in the gall-bladder (from Latin calx). It also meant a pebble used for calculating, or a small stone used as a counter in an abacus (Latin abacus, Greek abax). The abacus was an instrument used by Greeks and Romans for arithmetic calculations, preceding the slide-rule and the electronic calculator, and consisted of perforated pebbles sliding on iron bars.
I'm doing a research project using sensors in mobile smartphones, mainly the magnetometer. After taking extensive measurements on some pillars, in a hallway, that seem to give off a high magnetic field, measured by the smartphone's magnetometer, I now want to compare these magnetic field...
Homework Statement
Hi, well my task is to construct a DC motor. With 25w rotational mechanical output power. It cannot draw more then 5A current, and has to have 3 or more poles in rotation. The motor must be brushed/commutated. There is a max of 30v D.C. input. The motor needs to be built and...
Hai,
I have the following circuit:
http://img152.imageshack.us/img152/1848/powertransfer.png
My task is to calculate the power dissipated in the resistor, and also the power delivered by the V1 source.
Here's what i tried.
First i /dev/null'ed the second source and calculated the...
My abstract algebra book is talking about reducing the calculations involved in determining whether a subgroup is normal. It says:
If N is a subgroup of a group G, then N is normal iff for all g in G, gN(g^-1) [the conjugate of N by g] = N.
If one has a set of generators for N, it suffices...
Hey. I am currently doing a bit of revision for an exam and I am struggling on the following question:
I understand the whole voltage/current/power/impedance ratio stuff, but can't seem to find any information on calculating efficiencies using the resistances or the transformer core losses...
Homework Statement
Calculate the integral
Given \int_{C} \frac{e^z}{\pi i - 2z} dz = \int_{C} \frac{e^z}{z-\frac{\pi i}{2}} dz}
using Cauchy integral formula.
Homework Equations
What I know
\frac{1}{2\pi i} \int_{C} \frac{f(z)}{z-\zeta} = 2\pi i f(\zeta)
The Attempt at a...
Homework Statement
In using a ladder where the wall is smooth but the floor has a coefficient Us, why is it necessary to make the angle large?
Homework Equations
The Attempt at a Solution
I'm a little confused by this, because I would think that you would want to make the angle...
Homework Statement
An electron e^{-} and a positron e^{+}, each with a total energy of exactly 5000 MeV, collide head-on and annihilate to produce a tauon/anti-tauon pair, \tau^{-} and \tau^{+}, and no other particles.
1. For the electron moving before the collision, state or calculate the...
Homework Statement
Example nuclear fission:
{}_{92}^{235}U+{}_{0}^{1}n \rightarrow {}_{38}^{90}Sr+{}_{54}^{163}Xe+10{}_{0}^{1}n+Q
How much energy does such fission release?
Homework Equations
I'm given the values of M({}^{235}U), m_{n}, M({}^{90}Sr), M({}^{136}Xe) but I've not...
Homework Statement
The binding energy of a nucleus is given by:
E_{b}=a_{1}A-a_{2}A^{\frac{2}{3}}-a_{3}Z^{2}A^{-\frac{1}{3}}-a_{4}\left(Z-\frac{A}{2}\right)^{2}A^{-1}\pm a_{5}A^{-\frac{1}{2}}
For a given set of isobars, A constant, E_{b} will be maximised at the value of Z that satisfies...
Homework Statement
{}^{241}_{95}Am produces \alpha particles, which interact with {}_{4}^{9} Be to produce neutrons.
The Am sample emits \alpha particles at a rate of 70.0s^{-1} on June 16, 1996.
What was the activity on June 16, 2004?
Homework Equations
The half life for...
A mass retaining wall having a vertical rear face is 0.4 m thick at the top and 0.8m thick at the base, is1.6m high and made of concrete of specific weight 24kN/m3. It holds back Earth with a specific weight of 18kN/m3 and an angle of internal friction of 20˚. The coefficient of friction...
Two very large parallel conducting plates of very large length l, and width w are separated by a distance d. A current I=Jw flows to the right in the lower plate and to the left in the upper plate. Each of the two currents produces a magnetic field \frac{B}{2} between the two plates.
(a)...
Homework Statement
Helicopter Noise Transmission
[i]It is planned to introduce a regular helicopter service from a helipad at ground level in a hospital premises. There will be four arrivals and four departures per day but never more than one arrival and one departure in any hour. There is a...
Dear memebers of this community: Although I am newbie in using ABINIT I though I understood the basic features of it until I confront myself to the example of positron calculations (/abinitx.x.x/tests/v4/Input/t95.in and /abinitx.x.x/tests/v4/Input/t96.in ). I found that for running that test...
Hello;
I have never really come across vectors before in physics, so could someone help me out? For example, what would be an example question and a calculation involving this;
\phi_m = \int \vec{B} \cdot d \vec{A}
Correct me if I'm wrong but is this saying that the magnetic flux is equal to...
Homework Statement
In a photoelectric experiment using a sodium surface, you find a stopping potential of 1.85 V for a wavelength of 300 nm and a stopping potential of 0.820 V for a wavelength of 400 nm. From these data find the following:
a) a value for the Planck constant
b) the work...
Hi, for a project at college i am building an ice hockey puck launcher for the development and training of ice hockey goaltenders. I am planning on using two wheels rotating in opposite directions to launch the puck. The pucks will be fed in by a pneumatic cylinder that is powered by a...
Hi, I'm working on a commercially available PEM fuel cell and I'm trying to calculate the theoretical voltage of the cell:
The only electrochemical reaction considered is H2 + 0.5O2 --> H2O
And I understand that I need to use the Nernst equation:
E = EO - (RT / 2F) ln (PH2O / (PH2 *...
Homework Statement
There is an unstayed mast which is 3m long, supported at the bottom and at 0.5m from the bottom.
Sail area is 10 m^2, design wind speed is 50 km/h.
It is made from glass epoxy composite.
The base fiber is 300 g/m^2 glass textile. E-glass, 2/2 twill.
The inner diameter...
Hi guys,
I need to figure out the crushing force of a concrete crusher. Here's a pic to help illustrate:
I have 2 questions:
1) Would the crushing force on the concrete be 2*Ft or only Ft
and
2) Would the force exerted by the cylinder on each jaw be Fc/2 or Fc as shown.
Thanks...
I am trying to self-teach myself Fortran for an undergrad research position. A basic program that I am trying to develop is something will open a file, read a single value from a large table of data, do some calculations with it, and print it into a new file. I was hoping to get a little advice...
Homework Statement
a magnet that weighs 2.6 grams is dropped through a 1.53 metre tube. the average time taken for it to go through is 1.59 seconds.
I need to find the strength of the magnetic field and the currentHomework Equations
Fg=mg
B=F/IlsinthetaThe Attempt at a Solution...
I have been trying to find the concentration of copper in a copper sulphate solution and i was wondering if someone could check my calculations and maybe set me straight on a few things. Rep will be given of course.
Titration
I put 25cm^3 of copper sulphate solution into a conical flask, and...
Homework Statement
The Fourier transform of a function f(x) is given by the product of the Fourier transforms of cos(\alpha x) and e^{-|x|} ;
f^{~} = F^{~}\left[cos[\alpha x]\right]F^{~}\left[e^{-|x|}\right]
Find f(x) and show that it can be written as a real function.
Note: Do...
Homework Statement
Prepare 500ml acetic buffer with a concentration of 1 M and a pH o 6.0. (pKa for acetic acis is 4.76; molecular weight for actetic acid is 60g/mol and for sodium acetate is 136g/mol)
Homework Equations
The Attempt at a Solution
I have tried the Henderson...
Help with specific rotation calculations (urgent)
Homework Statement
I need help determining a sugar in solution based on the specicific rotation i gained through the required calculation this was done at 589nm Homework Equations
[α] = σ/cl
The Attempt at a Solution...
Suppose rabbit populations grow exponentially with a growth rate of 20% per year. If P(t) is the population at any time t and 1000 is the initial (t=0) population of rabbits, what is the population of rabbits in 10 years?
Use the DE model: P ' = kP with k = .1 and P(0) = 1000.
Plz help me
Heyhey,
I am currently doing my final year masters project which involves testing rotor blades. I am performing a stress analysis of the blades. I will be using FEA software, but I also need to do some hand calculations. I have been looking for formulas for a while now, but I am unsure which...
So, like quite a few others on this forum, I am building a trebuchet for a school physics class.
While I am really enthusiastic about the project (who doesn't love giant medieval war machines?), I may be a little bit over my head in the calculations.
So I hope I can give enough information...
Homework Statement
1. Consider the point P at position ⃗rP = (−3.0 mm)ˆı + (4.0 mm)jˆ. Give an expression for rˆP , the unit vector in the direction of ⃗r.
2. Consider the point P from exercise 1 and another point Q at position ⃗rQ = (8.0 mm)jˆ. Give an expression for rˆPQ, the unit vector in...
Hey guys, I have been working on some calculations to help me with sniping in airsoft. I am working figuring out the angle of inclination I would need to hit targets at different ranges being only a rough outline (I am not too worried about getting into the various calculations such as for air...
Homework Statement
1 litre of a monatomic ideal gas starts from an initial state (i) at T = 300K and P = 10^5 N/m^2. It (the gas) is changed to a final state (f), such as that its pressure decreases 20% and its volume double.
a) Draw a PV Diagram mark its initial state and final state...
Homework Statement
A 4.9-µC point charge is located at x = 1.1 m, y = 3.1 m, and a -3.9-µC point charge is located at x = 2.1 m, y = -1.9 m.
(a) Find the magnitude(inkN/C) and direction(in degrees) of the electric field at x = -3.2 m, y = 0.9 m.
(b) Find the magnitude(in N) and...
Homework Statement
I have been given the following load-displacement plots for the same specimin with two different crack lengths. The lines are identical up to a load od 750N
i need to calculate the area of the blue shaded region to obtain a value of Jc using a separate equation...
Homework Statement
an antelope moving with constant acceleration covers the distance between two points 70.0 m apart in 7.0 s. Its speed as it passes the second point in 15.0 m/s .
a) what is its speed at the first point?
b)what is the acceleration?
Homework Equations
what do you...
I'm currently studying physics at A-level, and for particle physics I'm fine about the theory of the equations, I remember what equations to use etc, but I can't seem to get the right answers from my calculator.
For example, when working out the specific charge of a carbon ion with Z = 6, A =...
My understanding is that the folks who do particle mass calculations using the formalism of a lattice get results that fit measured values well without using a Higgs field. Is this correct? If so, do we have any use for and/or reason to believe in the Higgs field/particle?
Hi eveyone,
I am working on project of designing a heat exhanger in order to recover heat from a exhaust of Stationary IC Engine producing power of about 2 MW. The fuel used for combustion is CNG. Most of the books I read, tells about the products that will be produced in exhaust after...
So there it is me trying to program some simple physics for flying ball. I have done some research and generally I was always understanding physics very well. But what is happening in my application is not understandable for me, even tho I have checked everything twice and I think everything...
I know this seems like a homework question but the last time I was in a physics class was <ahem> 1982.
For product testing reasons, I have fabricated a (rough, very rough--no laughing at the fabrication/welding) 'repeating pendulum hammer'. Please see "test rig diagram.jpg"
Distance from A to...
Hello all,
This is my first forum post and any problems with the post are openly accepted.
I would like a sanity check on my approach to this problem. I have built a permanent magnet three phase AC generator. I need help in properly calculating power values for this. This is for...
Ok, not really a homework question, just something I am confused about. Hopefully it belongs here.
Alright this is in my lab book:
The overriding consideration for significant figures in computations is that a result should not be quoted with a precision higher than the absolute...
this is a power calcualtion using 1 magnet pair with the turbine turning at 1 rpm..34 inch diameter rotor. i hope someone else can make sure I am at least doing it right, and i need help converting my single phase numbers to 3phase wye
________________________________________
coil info...
We were preparing Alkene from Alcohol & were asked to calculate percentage yield.
We used 13.5 ml Cyclohexanol with 13.5 ml water & 7ml Sulfuric acid.
To calculate % yield,i need theoretical mass..
So i was calculating no.of moles of cyclohexanol & cyclohexene (the product) to get the...
Homework Statement
I have to compile a report for a project on the science behind a boat. Its a really open ended aissignement, I have no ideas where to start or what equations to use.
I need the boat to go 20mph and therefore calculate what engine power I will need to make it reach that...
Homework Statement
I'm trying to find the acceleration due to air resistance in x direction and acceleration due to air resistance +gravity in y component.
given variables
m-0.14273(baseball)
Cd=0.4
Vi=20m/s
angle= 45 degrees
Basically, I have to program a projectile motion program...
I am usually bad with calculations, so please help me out.
It's not a homework, merely my interest...
So, let's say I have a tube with some air pressure in it and I open up one end of the tube so the pressurised gas exits it in one direction... (basically a rocket)
Pretty simple, huh? :D...
Hi there,
Had a fair bit of hoework my first day back with no answers. Would anyone mind looking over these to see if i did them correctly?
Thank you for your time.
http://img42.imageshack.us/img42/5117/46730937.jpg
http://img35.imageshack.us/img35/4489/56478985.jpg...
i am trying to make a piece of stainless steel of varying thickness bend in such a way that it creates a cam profile in much the same way a fishing rod works.
for example if the thick end has a 5mm by 10mm cross section and the thin end is 1mm by 10mm crosssection and the change in thickness...