Loss Definition and 793 Threads

Hi all, I have a copper pipe which has 15mm of insulation on it. The outside radius of the pipe is 17.2mm and the inside radius is 14.8mm. The insulation will have a conductivity of 0.025. I found an question which is meant to show an equation for the heat loss in an Insulated Cylinder or...

This is a past exam paper Q. I think i might be missing info though. For i) i use q=UAdT A= 35m2 dT= (80-20) They haven't given U but if i know answer should be 1,050W So if i set U to 0.5 (0.5)(35)(60) = 1050W Am i missing something or could I calculate U with the info given? Also ii) Use...

Unsure on whether I have done part d) right for this question Here is what I have done already: Any help would be great! Thanks

Here is the Q below This is what I have tried so far. I ended up getting a value of 1772.4 watts Is this the correct way of doing this problem?

Flow delivered by a pipe can be calculated from input pressure, inlet geometry, pipe length, and a flow coefficient related to pipe cross-section, shape, and roughness. If we create an example of a pipe attached at the bottom of a self-refilling standpipe, which automatically supplies a...

I do not know where I am doing wrong. I asked a tutor, he said I was doing it correctly. Below is my work. Please help! Net loss by radiation in 10.0 mins is 74.8 kJ

the Buchner funnel is used often in the lab, but i was wondering if there was a great enough transfer loss in the filter paper to switch to an alternate funnel for filtering by suction. I've looked into sintered glass funnels but i don't know if it would have the same transfer loss since the...

That's what I've got , but I want to confirm my answer. Any help would be greatly appreciated !

Hi, If it is assumed the temperature of a shower is to be 43°C and the electric shower consumes 50 litres of water at that temperature, then the Energy required for an electric shower would be: QElectric Shower = mcΔT QElectric Shower = 50 * 4.181 * (43-10) QElectric Shower = 6.89945 kJ or...

Summary: Pipe Testing I need some help on how to calculate PSI loss to gallons per hour? We will be testing this 8" PVC line at 150 PSI for 4 hours. If the test gauge drops 10 PSI per hour, what is the formula to determine the gallons per hour lost? Thank you for your help.

Why does hysteresis loss cause heat and why the heat proportional the area of hysteresis loop?

We were discussing apparent mass loss in water in class yesterday. A student asked if apparent mass loss happens in water, does it also happen in air? And if it does happen in air then why do we not compensate for that when determining the mass of an object in air. I did some rough math trying...

I have an example from my machinery handbook which shows the kinetic energy of a pile driver and shows it will drive a pile some distance at a force until the energy is expended. The formula is (Average force of blow times distance)= Weight of object (driver) times distance it falls) Just...

Hi All, Recently, I have been struggling to seek a solution for a seemingly simple flow question and try to rationalize my thoughts with mechanical engineering knowledge I have acquired from school but none of them can make me feel comfortable about answering the phenomenon I encountered in...

Intuitively I fell like AC would lose more power long a long power line than DC. I will use a model to explain my perspective. Let me model a wire as a long straight, non-frictionless tube, about the diameter of a marble, filled with a row of marbles that are each connected to the one next to...

In the context of a forecast, I am currently working on Fisher's formalism which is part of a more general theory, that of information. My problem applies to estimating cosmological parameters from input data with the Fisher formalism and recipes to build a Fisher matrix. The context is...

The plate is in inclined position in a chamber where the air flows from bottom to top.

Other than with black holes, are there any other natural ways that quantum information can be lost, and thus jeopardize quantum determinism?

I know that water losses pressure as it move throw a pipe due to friction. Does that mean that if we have two elevated tanks separated by a great distance but connected throw a perfectly horizontal pipe ,and then we fill the first tank with water till it reaches a certain hight, then the hight...

I am not really worried about the numbers, but more about the simple concepts with head loss in these pipe flow questions. I want to confirm that head loss just means the change in static head, right? I have been advised that for a problem like this, it is nothing more than the conservation of...

Hi, I'm working for a company that want me to calculate something for them. I haven't done physics since A level so have forgotten a lot of it and am now very stuck! They want to know the kWh per year they will be saving by reducing their heat loss (which they have given me in watts per meter)...

Hello! I want your help for core losses on how to calculate core loss on a toroid core?

I understand the basic way of doing it if no energy was lost, but because it is and it adds this whole component of projectile motion I'm feeling a bit lost. At first I wanted to time how long it took from the top of the ramp to when it hit the ground, but I couldn't figure out a way of making...

Homework Statement Calculate the insertion loss of the T-network given the values: Rs = 75Ω Rl = 100Ω Ra = 13Ω Rb = 13Ω Rc = 213Ω The transmission matrix and Network are below: 2. Homework Equations The Attempt at a Solution Constructing the matrix: A = 1+Ra/Rc = 1+13/213 = 1.061 B...

Well, I've been trying to design a microhydro power project, and I contacted a supplier on Alibaba and we're a bit at odds about the recommended transmission voltage, I'd like to go with 480V and a transformer back down to 120/240V on the other end, their 'engineers' say this isn't necessary and...

Suppose some protons are impacted on a Lithium target to produce neutrons with energies close to the proton energy. If one considers Energy-loss due to proton-target collision (ionization of the target atoms), will this kind of energy loss influence neutron energy spectrum? I am asked by my...

Hello, I just had a little debate with my professor after taking my final exam. He had given us an additional formula sheet at the last second (hand written on the projector) which confused me. The question was a 7 MeV neutron collides with several U-238 atoms before reaching 2 MeV. How many...

Homework Statement Homework EquationsThe Attempt at a Solution I have posted the whole solution so it is more complete, but I really only need help with part c (I think) My output power is higher than my input power, I'm not sure where I'm going wrong

Homework Statement Problem: An object with mass 2.0 kg slides down a low-friction incline and its speed measured at the bottom is 2.7 m/s. The object starts sliding at a height of 0.50 m over the tabletop and its speed is measured 0.10 m over the tabletop. How big is the percentage energy loss...

Homework Statement Homework Equations y1 + P1/##\gamma##+v1/2g=y2 + P2/##\gamma##+v2/2g+hL The Attempt at a Solution I used the above equation and assumed that P1=0 and both velocity heads are equal. Is that valid? However I did not need to use the geometry of the pipe so I think I am doing...

What happens to the kinetic energy when an object is disintegrated? Does it survive? For example, if I throw a baseball at the sun at 100 mph, I will get X amounts of heat energy released and X amount of light as it burned up before contact. If I threw another baseball 100,000 mph into the sun...

Related to an engineering project I will be working on. The situation is that essentially I will have a closed cylinder (5.5 in x 26 in) with a small 15mm hole on the side (not on a circular face), which allows the air inside to be at equilibrium pressure/temperature with the outside. Then a...

I am building a rainwater collection system and want to know how much higher the tops of my PVC downspouts have to be compared to where the water exits into my rain tank. Or, how tall my rain tank can be if my downspouts are 10 feet tall. Let's say that the rain tank and home foundation are...

Homework Statement We want to calculate the rate of air loss from a space vehicle (module) if a meteoroid punches a hole in it. Assume the module is sealed off from other modules. It is shaped like a cylinder roughly 4 m in diameter and 10 m long. The hole's area is a cm2. The hole is punched...

Hi, I'm trying to simulate the process of charged particles attenuation in matter (like this) by a montecarlo-metropolis algorithm in Python. I thought that I could use for the number of particles at thickness ##x## the formula ## N (x) = N_0 e^{-\mu x} ##, so the probability in this case will...

Hi everyone I'm new around here and I wonder if anyone can help please. I'm taking hot air off the chimney stack inside a factory at a temperature ranging between 700 and 400 degrees going through a 4 inch stainless steel pipe with 3mm wall thickness. This pipe line will be about 35 meters long...

Hi all, Quick question: What do you guys use as your reference for minor head loss coefficients (k). I'm sure those with more experience have their own database/excels of k values found over the years. I have been personally using a combination of my Hydraulic Engineering Textbook and Google...

Hi all, I have some problems to understand how to calculate the transmission loss at long distance, which model do I have to use? I was looking into the energy flux model (Weston model), but I didn't understand at what range I should switch from "mode stripping" to "single mode". I am working...

Homework Statement Find the admissible current density Jadm for a wire that has no insulation and also for a wire that has two layers of insulation and compare it to Jadm for the case when the wire has only one layer of insulation.2. The attempt at a solution and equations In the image I've...

How can I calculate the loss of potential energy when forces are applied but no motion in the system occurs? Here's an example: Let's say I build a battery operated car that is set to drive forward, but I put it right in front of a wall. It attempts to drive forward, but instead it just pushes...

Homework Statement why is there a loss of energy in DC circuits and power loss is reduced in AC when transmitted Homework EquationsThe Attempt at a Solution Loss of energy in a DC circuit is due to the resistance of the wire cauing the wire to heat up therefore energy is being lost by heat...

Homework Statement similarities and differences of AC and DC current in simple circuits. Outline using diagrams and a clear desciption the loss of energy in DC circuits and power loss reduction of AC when transmitted. Homework Equations N/A The Attempt at a Solution DC loses energy over long...

Homework Statement A careless farmer sends this sheep out to graze on a very cold winter day when the temperature is -10oC. The sheep's coat has a thickness of 4.7 cm and a surface area 1.3 m2. Calculate the rate of heat loss from the sheep on this cold day. Assume that heat is lost only...

Hello all, I want to know about turbo alternator real power producing capability under loss of excitation condition. Normally in salient pole rotor have capability to supply real power under field current=0 condition, as there is reluctance power developed. But what about non salient pole...

Homework Statement Is the following conclusion correct? Assume there's an equation with vectors on both sides. Taking the dot product of this equation with vectors on both sides loses information, but information will not lose when taking dot products with higher rank tensors on both sides...

<< Mentor Note -- poster reminded to use the standard Template >> Question Three A pipe of outside diameter 200 mm is lagged with an insulating material of thermal conductivity 0.06 W m-1 K-1 and thickness 75 mm. The pipe carries a process fluid at a temperature of 300 °C and the average...

Apologies upfront, I have a backlog of PF threads I have created not replied to...I will endeavour to do so when I can. So I've read that IGBTs are more efficient than MOSFETs for lower than 20kHz frequencies (and are capable of use for high voltage rating and better performance than ordinary...

Hi, I am currently having an issue and hope someone can help me out! I have a Digital to Synchro card on my server that will transmit the synchro signal voltage to various component. For this issue in facing, System A takes in 4 sets of data. Thus, there will be 4 sets of S1 S2 S3. At System A...