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 know the formula T=F*D but having problems wrapping my head around this problem.
I want to direct couple a stepper motor with a .5"D shaft to a .75"D ballscrew.
The motor has 400 oz inch torque but since the motor shaft is .5"D or .25" radius How do I calculate the Torque at .25" radius? I...
Hello PF.
I wanted to optimize time expenditure on some calculation that I'm doing. A natural way to do this can be by computing parts in parallel.
Now when I say "parts" I don't mean that some computations are wholly independent of other computations. My situation is that I have a bunch of...
1) I'm not sure how to solve this question
A 20MVA induction motor connected at 13.8kV draws a load current of 1.0 p.u, 0.85 power factor lag. Calculate the rated load current in Amps and the real power and reactive power drawn by the motor. Express these quantities in per unit form using...
Looking to understand Fatigue calculations for stainless steel seamless tubing
Problem:
Material: 304 Stainless Steel tubing (.375 OD, .072 wall) per ASTM specifications used at 158F degrees maximum
Ambient UTS 515 MPa, YTS 205 MPA, temperature de-rated per MIL-HDBK-5J to UTS 473.8 MPa, YTS...
I am trying to determine the expected heat exchange between flowing ground water in gravel/clay soil (that runs on top of blue clay) and glycol fluid in plastic pipe (1 1/4"). For my current interest, estimated ground water temperature of 60 degrees seems best. I am trying to determine the...
Hi all
I am struggling to work symbolic math calculations with Fotran 95 in the Silverfrost ftn 95 plataform.
Say you want to calculate c=a+b but without initializing "a" or "b" to get a value "c", but rather print out or obtain the actual generic expresion "a+b"
I have tried to solve...
This isn't a homework question per se, but more of a coursework question. Specifically, I'm a bit at a loss as to how to go about learning a particular section of the coursework for a physical chemistry (i.e. thermochemistry) class I am taking. The section in question is that pertaining to...
I have been given a physics assignment which requires that I go over the physics of why 40km/h is a better speed to be followed in a school zone rather than 50km/h. (must include calculations for stopping distances etc.)
I used the formula Vo ^ 2 / 2 x μ x g.
It should give me the stopping...
Homework Statement
I have a physics lad research that's due tomorrow, the overall process is to work out how much potential energy will be stored in a bow, and the efficiency of the bow.
First of all, I have a graph, with the plots Force Vs. Displacement (of a weight 'm' on a string). We...
hi so i had to build a catapult and it's very small, but i need to find the total velocity of the ball upon impact and the maximum height reached. You might need to explain a little bit because I tend to not get things when they are vague so please post more than a formula. Please and thank you...
I tried posing my question by using some Latex features here, but I could work faster by using Word coupled with what I could use from Latex here. When I tried putting the material here from Word, it didn't work out, so I'm attaching a pdf of my question. The reference to IMO is the...
Hi Folks,
Not the best at this so hoping somebidy can help me.
I have a 67.4 litre vessel and I'm filling it with SF6 to 6Bar. Can I work out how much SF6 I'm using in litres?
Is this a dumb question? should nI be asking what weight I'm using.
I've been asked to supply usage in litres.
Hi everyone,
Long time reader first time poster. A little background on myself, 4th year in the field of ME mostly in simulation and analysis (FEA).
I am currently working on a project of a high speed electric motor. I am putting together all the losses from the rotating motor (Copper...
Homework Statement
A duct of length 5 m at 38 Degrees inclination to horizon with a cross section dimensions of 0.3 m X 0.4 m is carrying 2 kg/s of a heavy gas at 10C and 1.2 bars and delivers the gas flow at 50C at the end of the duct to a horizontal pipe section. i) Calculate changes to...
Hi, ok, so the task is to define the thickness of th weld, the so-called a-dimension. If the welds were either vertical or horizontal, I'd have no problem, but they're not. So do I divide the force into components or perhaps the welds? What about how to calculate the moment caused by the force...
Hello,
I need to find the bending moment and forces at the mid point cross-sections of two separate beams connected together. One is a horizontal beam connected to the top of a vertical beam that sort of look like this:
H========
H
H
H
H
There is a UDL of 10kn/m on the top member, with the...
HI i am a student from Singapore , and i was told to calculate the amount of hot water needed to supply to a house. The design brief stated
1)Deliver 15 gallons of water at average 110°F (43°C) temperature within 10 minutes; 16 water draws during 1 week
2)Dishwasher: Successfully wash five...
Homework Statement
In a high school project we have been given the assignment to design the mechanism to transform the a rotary motion into the oscillating of a wiper blade. I'm a bit confused as to how to go about the problem..
I have been given that there is a closing force between the...
Homework Statement
Hello everybody, I have a problem dealing with complex circuits, especially those that have extra symbols (transistors, earth, V_in, V_out). Hopefully somebody can give me helping hand. Thanks a bunch.
This is the link to the problem which is on page 11 (the first one)...
I have this conveyor which I am trying to automate i.e. It runs for 5 secs and have a pause of 3 sec, this process is continuous.
I am creating a mechanism where I have a gear of dia 200mm which is fixed (i.e. I can't change its dia) and it is attached to a conveyor.
Now I am introducing a...
Homework Statement
A Cassegrain telescope has a 500mm diameter , a focal length of 5000mm and a central obstruction of 80mm diameter.
Calculate:
1) the magnification with a 25mm eye piece
2) the light gathering power compared to aye of 5mm in diameter
3) the angular field in the sky if the...
Hi everyone!
I'm trying to do the classic calculation of the coefficients of transmission and reflection at a surface, but for a uniaxial crystal. I'm doing the simplest case, in which the optical axis is normal to the reflecting surface. Here is a simple diagram of what I'm trying to do...
Homework Statement
Basically, I need to understand how to calculate Irms and I*rms given a Vrms and an impedance Z.
Example question:
Given Vrms = 120 V at an angle of 30° and an impedance of Z = 10 Ω, find Irms and I*rms.
Homework Equations
How exactly do I solve for Irms and...
In the diagram attached, the 3 resonance structures of arenium ion bonded to H electrophile are shown.I labelled the carbon atoms in one of the structures for convenience.
From the diagram, the A and B carbons, and D and E carbons, have a double bond between them for two of the resonance...
I'm trying to find the equation of a parabola that goes through any three given points in the x-y plane denoted by (a,b), (c,d), and (e,f), which would be considered givens in these calculations. I need the form of the equation y = Ax^2 + Bx + C where A, B, and C are unknown.
I have gotten as...
Hi guys,
I just wanted to know when to use ωxr and when to use rxω when we're making vector based calculations. I realized that when reversed te calculations tend to differ a lot.
Thanks for the help in advance!
hi, not sure if I am posting in the right section, had a good look through the search option but cannot find what I am looking for, probably because I am being stupid..
im working on some simple beam calculations, I am a studying architecture, however I am trying to get my head round load...
What is the equation I should be using for the following question:
At 298K a cell reaction has a standard emf of +0.17V. The equilibrium constant for the cell reaction is 5.5 X 10^5. What is the value of n for the cell reaction.
Grateful for anyone's help!
Homework Statement
4-bromotoluene was synthesized and purified by distillation. There are 5ml of the crude product. A fractional distillation is being carried out in a 100ml round bottom flask. Assume that the volume of the column is 16ml. Determine the number of moles of 4-bromotoluene that...
Homework Statement
Using matrix algebra calculate the voltage expected across each resister in the circuit diagram.
Only need the simultaneous equations.
The Attempt at a Solution
-15=6800(I_b-I_a )+2200(I_b-I_c)
15=2200(I_c-I_b )+8200(I_c-I_d)
-25=8200(I_d-I_c )+4700I_d
Thanks for any help.
Homework Statement
A lamborghini's breaking speed is 6.7 times that of its acceleration. The total time taken to go from 0 to 100 and back to 0 is 13.7 seconds. What is the displacement of the car?
Homework Equations
Unsure at the moment
The Attempt at a Solution
So, you divide...
(i) Obtain the scale factor a(t) and redshift z when the energy density of matter and radiation were equal.
(ii) Next use the a(t) relation for a matter-only universe to estimate the time of matter-radiation equality.
(iii) Repeat (ii) but using the a(t) relation for a radiation-only universe...
Hi,
I am a PhD candidate doing some research on origins of field theory but my background is in E-field and power electronics and not astronomy. Looking for someone that might want to co-author a paper on the flyby anomaly or more specifically can help me check whether a prediction has any...
Would the efficiency calculated using the P output/P input x 100 get the same answer as calculating the efficiency using the RMS input and output values? If so why?
Homework Statement
The following table gives some specific acoustic impedances
Tissue or Medium Specific acoustic impedance
Air 0.00044 x 10^6
Fat 1.38 x 10^6
Water 1.5 x 10^6
Brain 1.58 x 10^6
Blood 1.59...
Would really be a big help if someone could look at my drawing and verify what I have come up with.
Basically pulleys with cable wrapped around then and a weight hanging off the bottom. What I am interested in is what the wight pull at the pull scale would be and if their is any left or right...
I would like the formulae for calculating the distance created bewteen products transferring from one conveyor to another with a line of products moving at x M/min transferring onto a conveyor running y M/min. I need to be able to calculate what the gap will be between the products as this is...
Hello Everyone,
I am a PhD student working in the field of mineral and material processing. One part of my project involves use of DFT calculations to study adsorption of small to mid sized molecules on mineral crystals.
I am using Gaussian 09 simulation package and currently I am in the...
me and my partner did an experiment of turning copper coins into 'silver' and 'gold'
we used this site or the info:
http://www.nuffieldfoundation.org/practical-chemistry/turning-copper-coins-silver-and-gold
But we're having trouble with knowing how to make the calculations of :
How much...
hi,
i have some problems in power train calculations for a small race car has a chain instead of crank shaft converting motion to the rear side, calculating torque on the axle and wheels, forces and the acceleration of the car.
So, can anyone help or mention a guide reference ?
thank you
Im working on a little project where I am attempting to generate steam from a hot gas pipe. I haven't measured the rate of flow or temperature of the fluid as of yet, and I haven't decided upon the choice of material, but I'm looking for some calculations to start.
My plan is to wrap a water...
I want to make sure I understand what I am reading in various spec sheets when they quote their noise measurements and I hope that you-all can confirm that I am on the right track.
Take the OP27 Op-Amp as an example, which is described as a low-noise precision operational amplifier...
Hi Guys :
I have been reading about torque and gears and not being an engineer or physicist would like to know if my thinking is correct in the following example
Ok so Say I have a hydraulic motor and it generates 3000 ft lbs of torque and it is going to be turned at 650 RPM (tractor...
Homework Statement
I've been following closely a book on PDE's working through lots of steps but here I'm stuck.
Basically I have the relation f(x)= \sum _{n=1}^\infty F_n \sin \left ( \frac{n\pi x }{L} \right ). I want to calculate the Fourier coefficients F_n.
I look at the definition in...
Homework Statement
I am in a beginner c++ class and this is my second program. I am having trouble getting the calculations to output correctly. I'm not sure what I'm doing wrong here, maybe somebody can help.
Homework Equations
The program takes user input data for points in a...
Hi,
How do I develop and train to do quick back of the envelope calculations? How have you developed these techniques? I am not quick in it and make silly mistakes.
Im about to hand coursework in. Its the youngs modulus of copper wire
We added 100g weights and measured the extension using a traveling microscope.
for example at 0.900kg the wire extended by 6.36cm
my calculations are
Diameter = d 2.7x10-5 m
Cross section area A = Pi x d...
Lets assume that all properties of a piece of piezoelectrical material are known, how should the analytical calculations be performed if the goal is to convert a vibration into electrical energy? What I'm looking for is the theoretical output voltage one can achieve for a known vibration.
To...
Homework Statement
Find nonzero scalars a, b, c, such that au+b(u-v)+c(u+v)=0 for every pair of vectors u and v
This isn't a homework question, more of a conceptual exercise, but I want to understand it thoroughly.The Attempt at a Solution
I've gone to u(a+b+c) + v(c-b)=0
then I couldn't quite...
If I take the Dot Product of two vectors, say A and B, I get: AxBx + AyBy + AzBz
And then when I add those terms, I get the magnitude, right?
So when one of those terms are negative, that means I could end up with a negative magnitude?
I thought magnitude had to be positive.