Calculation Definition and 1000 Threads

I am wondering if someone can show me how to calculate the exit speed of an object if it is dropped into a container which is spinning at 5000 rpm and has a radius of 120mm. Let us assume the object weighs one gram. I am building a machine for wear testing. rock/water is supplied to the centre...

Please,I am working on the criticality calculation of an homogeneous finite cylindrical reactor core using four-group diffusion equations. I have been able to discretize the multigroup diffusion equations using the finite difference method(FED). But I am stocked on the iterative method to...

Homework Statement I need to calculate the power for phase A, B, and C so that I can determine the total power into the system. I have measured the following data: VA magnitude = 117.7 [v] VA angle = 0° IA magnitude = 7.5 [A] IA angle = -25.5° VB magnitude = 117.7 [v] VB angle = -124.1° IB...

Okay, it's not easy for me but probably for you ;) Hello first of all! I have two questions: 1. Why is there a minus before the expression in the red circle? 2. How did the x((n-1)-1) in the last line come to be?More precise: I understand the first parts. It's the random walk and x signifies...

Stuck on a question in my Construction Materials coursework. Not asking for anyone to solve it for me but would be grateful if someone could point me in the right direction: As far as i was aware, stiffness = force/deflection, data which is not obtainable in a hypothetical circumstance.

Hello everybody I am an architecture student working on a facade system and because I do not have much physics knowledge I stumbled across a question I can't answer myself: If my facade is actually a thin parallelipiped glass tank filled with water, how do I measure the temperature changes of...

Homework Statement At midnight (local time) on Dec 21st 2015, the Local Sidereal Time at Palomar Observatory, California, was 6h 27m. Palomar Observatory has latitude 33◦ 210 2100 N, and longitude 116deg 51arcmin 60arcsecW. a) What was the approximate Local Hour Angle of the Sun at 23:00 local...

Is it possible to find the pressure of water that leaves a pipe of certain area/diameter given only the flow rate of the water itself? OR the requires piping diameter/area given the pressure that I desire. I'm trying to design a system that requires relatively high pressure (for spraying)...

I have what seems like a straight forward question, but am unable to find a formula. The question originates from my previous topic which was trolled: https://www.physicsforums.com/threads/blowing-up-a-balloon-using-centrifugal-force.848892/ Basically I have a 1.5m hollow length of 10mm tube...

I am looking for someone with mechanical engineering background who can assist me in making some calculations. I have an aluminum tray that is connected to a tripod and that supports a laptop. I want to get a lighter and smaller aluminum tray that can accommodate a tablet, but I don't know...

Homework Statement Calculate the ΔS° when 0.5 mole of liquid water at 0°C is mixed with 0.5 mole of liquid water at 100°C.Assume Cp=18cal/deg mole over the whole range of temperatures. Homework Equations ΔS=∫ Cp/T dT

Homework Statement [/B] a=12.26 +/- 0.08 b=0.25 +/- 0.05 e=1.2 +/- 0.2 Evaluate the uncertainty of following calculations Part 1. z= 5(ab/e) Part 2. p= 3e - b The Attempt at a Solution I attempted part 1 like this Δz/z = 5 (Δa/a + Δb/b + Δe/e) ... Calculated Δz to be 20 but the answer is...

Homework Statement I have an object of a known mass, and known dimension along one axis (length). Mass: 10 kg Length: 2 meters I wish to calculate what the mass of an object that is similarly constituted and shaped will be if it has a greatly expanded length of: 1,000 meters. I am seeking to...

Having difficulty remembering how to model a simple heat transfer equation for a liquid tank/piping system and wondering if anyone can provide some quick help. I have a 1000L tank of water that is heated by a 1kW heater (target temp of 43°C). The piping system (outside of the tank), holds 100L...

Suppose an object of mass m is hung in a steady state by two strings. One string makes an angle 60 deg. at the point of contact with the object with the horizontal line. The other string makes 45 deg. To find the tensions in these strings (T1 and T2) we take all Horizontal Forces or their...

Homework Statement In the attachment. Need to calculate azimuth of BC. Homework EquationsThe Attempt at a Solution I don't understand why the azimuth of AB would be given as 126 degrees when it is almost a complete revolution of 360 degrees. I calculated the back azimuth which would be...

Homework Statement What is the velocity of a rugby ball 3.0s after it is kicked vertically upwards with a speed of 16m/s? Give your answer to 2 s.f. Homework Equations SUVAT The Attempt at a Solution s = ? u = 16 v = ? a = g = 9.8 t = 3 Erm... v = u + at? 16 + 9.8 x 3 = 45m/s. Incorrect, try...

Hallo. So the other day I reviewed a bit of quantum field theory and went through the Compton scattering calculation. To no ones surprise it was fairly simpel if you have a nice list of identities for rewriting the base results from the Feynman diagrams. See for exaxmple section 5.3 in...

Attempting to determine the torque on the shaft of a pump. Known values are flow rate, RPM, and shaft diameter. 1. What other values are needed to make the calculation? 2. What is the equation I can use for this?

Hello Here is an uniform E filed distribution aperture antenna E and H far filed euations and here is directivity calculation approach my problem is why don't we calculate D with both E(theta) and E(phi)? My mean is: instead of using we should use because both of them are not zero in...

Homework Statement Hello everyone. A 4-way TV antenna amplifier has the following specifications: Bandwidth = 40-862Mhz Gain = 20dB Noise figure = 6 dB Max output = 85dBuV Input impedance = output impedance = 75 ohm Question 1: Calculate the required voltage on the input of the amplifier to...

Hi! I've written a novel in which my main character travels through time (into the future) 18 years. While the concept of time travel is necessary to the plot, the details are not. Meaning, the book isn't sci-fi, but contains elements that wouldn't normally exist in a contemporary novel, so...

Homework Statement The great Sumatra earthquake of late 2004 had a main shock with an M_w magnitude of 9.1 and a large aftershock in early 2005 had an M_w of 8.6. Calculate the seismic moment, M_o (energy release) of each earthquake. Homework Equations M_w = 2/3*log(M_o)-6.0 Where log = log...

Homework Statement A spherical drop of water carrying a charge of 3×10^-19 has a potential of 500V at its surface (with V=0 at infinity) (a) What is the radius of the drop? If two such drops of the same charge and radius combined to form a single drop, what is the potential at the surface of...

This question is confusing me, trying to find an equation for "tensile force" has left me confused since I've found no equation for it just for tension, tensile stress and tensile strain, just wanting to make sure I've not missed anything or done it incorrectly 1. Homework Statement At a...

Hi folks, I'm working on Fluka nowadays which you can found from here if you are not familiar. It's a very useful and widely used Monte Carlo simulation package. My main goal is to be able to perform total cross section calculation with it. So far, please consider I'm a rookie, I've done some...

Hi everyone, Homework Statement In the picture in attachment you can see 2 objects: "1" (it would be a door keeper) is able to move in direction "Y", "2" (it would be a lock latchbolt) is able to rotate around its axis. The 2 objects are in contact with each other. On the object "1" we have a...

I know two formulas which is to do with change in temperature,first one is : Q=mc(T-t) and the second one is E=sigmaT^4. My question is the difference between these two and where we have to use either of these?

Hello, I'm a student in mechanical engineering and right now, we're studying non Linear Calculation of Structures. We have a project which consists on evaluating one of the solutions to stop a tourism aeroplane CESSNA 172, like a cable to stop it when it lands. So we started our study with a...

Homework Statement y'' + 3y' + 2y = r(t), r(t) = u(t - 1) - u(t - 2), y(0) = y'(0) = 0. I need to solve this by convolution, which I know is commutative. The problem is that my calculation gives (f * g) =/= (g * f). Could someone please tell me where my mistake is? Homework Equations...

Hi, I have a question how to calculate the light emitted from a LED screen. The LED display is rated at 5000 nits. Total size of the display is 64sqm. (8m x 8m touching the floor) I would like to calculate the total light emitted, the light on the floor in front 1m away and the light on the...

Homework Statement A man is jumping up and down on a pogo stick. For the purpose of this problem, we will think of such a stick as being a (massless) spring with a guy + stick on top. We will assume that no friction is involved, and so in principle the guy could keep jumping forever. At...

Homework Statement I have two analog MEMS accelerometers ADXL337, ADXL377. The ADXL337 can measure acceleration upto +/- 3g (where g = gravitational acceleration) and ADXL377 can measure upto acceleration of +/- 200g. More than this much amount of acceleration, would create noise and random...

Homework Statement Muscle can be torn apart by a force of 100,000 N applied across an area of 1 m2. A 10 cm2 muscle therefore will be torn by a force of 100 N. If a student of average size were being lowered into a black hole of 1 solar mass, at about what distance from the hole's center will...

Firstly, I'm new to these forums, and I'm not sure what the prefixe in creating this thread is supposed to be... (i'm assuming it is to judge to question's level)? saw some threads without prefixes but i can't post one without... maybe i missed a stickied thread or a readme? Alright, so, first...

Hello, I am new to this forum but I have a question for you all. It is about the pressure in a system that changes when leakage changes. The test setup has to following components: - Air supply with 8-10 bar - Pressure valve that can be manually adjusted - A flow meter that measures the...

Homework Statement A spaceship with mass m = 800 kg moves freely in gravitionalfree zone. It moves with a constant velocity v = 1.5 km/s for t < 0. At t = 0 the spaceship is starting to break using a rocket acting on it with a time dependent force F(t) = Bt (T-t), where B is a positive...

#1 Round and round we go! You are constructing a centrifuge to use its spinning motion to act like increased gravity. (a) Find the formula for centripetal force. (b) Your centrifuge can spin at 35,000 rpms and your samples are placed 1.75 inches from the center of rotation. If the force of...

Hi, this may be a very trivial question but, When calculating energy, is it BE(products) - BE(reactants) or is it the other way round? I have been solving questions and the solutions were products - reactants for some and reactants - products for some. Also for mass defect , is it mass (...

Hey, I am attempting to figure out the optimal nozzle placement for an evaporative cooling tower. Now, calculating the theoretical coverage of each nozzle is obviously not a problem since I know the spray angle of the nozzles. However, since the water is injected at a much higher speed than...

Homework Statement Consider a point charge Q placed at point O.Consider any point p in the field of the Q.Charge q is placed at point p.Charge q is then moved from point p to s the distance i=between p and s is dr.Calculate work done. y Homework Equations ##dW=##-##F^→.dr^→## The Attempt at a...

An airplane takes off and flies 245 km on a course of 45.0° south of west and then changes direction and flies 175 km due south, where it lands. Find the displacement from its starting point to its landing point. I have literally no idea how to approach this, I worked with physics only...

Hello all, My robotics club at school will be entering the VEX Nothing But Net competition. We are beginning to design the robot and it's launcher specifically. We want our flywheel design to be two wheels on each side, on a horizontal line like this. We would squeeze the balls between the...

I built a spreadsheet to determine the flow and everything through a pump. I won't get involved with the first part just assume it to be correct and the gallon per hour/minute calculations are correct...

Hi. I have problem simulating this circuit in Multisim: (LTSpice) Here is scheme from Multisim: When I run transient analysis, I got this: ------ Checking SPICE netlist for Design3 - Saturday, September 26, 2015, 10:58:03 AM ------ ======= SPICE Netlist check completed, 0 error(s), 0...

Homework Statement Jack decides to create his own temperature scale. He places an uncalibrated mercury thermometer into an ice-water bath and records the mercury level as 20.0S. He then places the same thermometer above boiling water and records the mercury level as 170S. Finally, he divides...

Hi. Can somebody make a calculation for me? how strong do a magnet need to be to lift a mass of 75 kg iron 1 meter straigth up in 1 second. Best Regards morten

I am trying to solve the following problem for my graduate course in isotope geochemistry. If 1 g of 226Ra is separated from its decay products and then placed in a vessel, how much helium (cm3) will accumulate in the vessel in 60 days? Here is what I know. The decay series from 226Ra to Lead...

Homework Statement Find the limit \lim\limits_{t\to -1}\frac{\sqrt[3]{t}+1}{\sqrt[5]{t}+1}. Needless to say: No L'Hopital's rule, otherwise this thread would not exist. Homework EquationsThe Attempt at a Solution Have tried multiplying the fraction such that I get the difference of squares in...

hello. I have a ejection mold (steel) which has a bridge like mount which locates the handling eye bolts outward around hydraulic cylinders. I need to make sure the bolts in the bridge will not shear due to the sideways load when the mold is lifted or flipped 90degrees. Here is the known...