Loss Definition and 841 Threads

The following is the advancement of what I discussed in the link https://www.physicsforums.com/showthread.php?p=4274966#post4274966 Problem Statement To calculate Pump Discharge Pressure, Calculate the wattage for the pump Data : Water @ 85 Degree C Flow in for 24” pipe : 3010...

I have and as I said, I am on some version of the diet myself, though not for weight loss purposes. In rankings of Diets *generally* Atkins rates very low. The weight loss effects from Atkins are mostly due to the fact that carb restriction is a good way to lower calories. So it amounts to a...

I have three grid tie inverters connected to my grid thru standard AC plugs. The system pushes about 1kw to the grid during the day but during the night they draw a total of 45 watts from the grid. This has been confirmed by measuring the ac current in the ac cord with a multimeter and with a...

I have head loss (25.95ft) and converted that to pressure (17.19psi). I am trying to find flow rate in 3" sch 80 pipe coming from railcar at 25psi. So outlet pressure is 7.813psi. The fluid is 50% Caustic soda.

Hi, A current carrying wire creates a magnetic field around it, as shown here: http://courses.ae.utexas.edu/ase463q/design_pages/fall02/wavelet/3_sour8.gif As far as I am aware this usually doesn’t cause a power loss. Even if there is a flux on a nearby conductor there will be no power loss...

1. Problem Statement Transform equation 1 into equation 2 to show they're equivalent. Homework Equations *Please note that I added a subscript to each variable indicating the units. The Attempt at a Solution The highlighted constant shown in my attempt at the solution is...

Homework Statement The energy density (energy per unit area per unit time) arriving from the sun at the surface of the Earth is 1300 J/m2s. Calculate the mass loss of the sun in one year. (The Earth is about 1.49 x 1011 m from the sun.) Homework Equations ΔE = Δmc2 KE = (γ-1)mc2 The...

Considering the vibrational damping of bubble wrap. My basic premise is that there are three main contributors to the damping effect: 1) Surface tension of the sheet structure and the bubbles themselves when subject to applied force causes dissipation of force away from applied direction 2) The...

I need some help!My problem is a problem of moving boundary with loss of mass... I started to use COMSOL and I need to simulate one plate with a hole on the center. And this hole is increasing with the time according to one equation (like a velocity, in m/s) which depend of the stress. Someone...

Hello, I'm working on a project at which a large amount of current is being passed through a low voltage system (48 Volts). In one part of the system, there are connectors rated at 12 Volts in which the 48 volt DC current is passed through. How much power loss might I be suffering here...

I have a lab in which a moving marble collides with a still one. What changes could I make to reduce the amount of kinetic energy loss in the collision? The track for the marbles is a piece of card stock paper. I was thinking: -Use two tubes as a track which will reduce the amount of...

reversal of hearing loss reversing/curing hearing loss Sensorineural Hearing Loss moe & holycow1, since you made these queries, recent research suggests certain types of hearing loss is reversible; specifically sensorineural (that has resulted in senescence of receptor hair cells in the...

In any common chemical reaction that releases energy, say the reaction 2H2 + O2 = 2H2O, what mass is converted to energy via the E = MC2 equation? What sub-atomic particles are converted to energy during ordinary chemical reactions? I was taught us in HS and under-grad chemistry classes that...

I'm new here. I am working on a fictional space commerce system using containers to transport things between planets. The container size is 4x4x8 meters and most often it would be colored but call it grey for the purpose of the question. I don't know what you would make it from, I suppose...

Hi, I'm trying to put a long open-ended debate to rest. For those who don't know, the EGR, Exhaust Gas Recirculation, system takes some of the exhaust gas and reintroduces it into the intake manifold. From what I understand, at 1600°C NOx is formed because air molecules, nitrogen N2 and...

Hello all. I've been teaching myself C++ programming and had an idea for a project. I am building a calculator for the heat loss of a room when an outside door/window is open. I'm currently writing out the functions I need to make this happen... Now what I need help with is this. I can't seem to...

Hi all, i have a problem here I need to solve asap. Homework Statement I need to find out the Time it takes for 6900 gallons of WATER to go from: 55 deg F. to 32 deg F. 55 deg F. to 20 deg F. ambient air set at 20 deg F. if needed The heat loss rate is 750 Btu/Hr/degF. Homework Equations...

Homework Statement Here is the question with the solution The Attempt at a Solution First off, where is the energy loss going into? What causes the system to lose energy? Secondly what is the term I circled in red? The one with 0.22948, where does that come from? Thanks!

Hello, Homework Statement I am trying to find an expression for the energy transferred into heat due to friction between layers of viscid fluid. I am provided with the following diagram (see attachment), and am instructed to first find the force at both ends of the cylinder exerted on the...

Hello all . Why photon increase energy and frequency when falls in gravitational field ? or decrease it's energy when escape from a black hole ?

Why exactly is it necessary for angular momentum to be lost by a mass if it is to accrete around a black hole? the mass is decreasing its radius, so it speeds up: thus angular mometum is conserved. But everywhere it is saying that 99.99% of the angular momentum must be shed for accretion to...

I was recently informed that AC is the preferred method of transmitting power because it suffers significantly less power loss going from the generating station to where ever it needs to go when compared to DC losses. In my introductory electricity class we learned that power through a given...

Homework Statement I have a stove, basically a metal drum which is the fuel chamber. Think of a hobo stove, just a metal drum with a fire in it. This stove creates convection heat via exhaust, and conductive heat to the metal drum itself which "slowly" releases the heat from there...now, I...

Homework Statement A small body is set on the surface of a smooth sphere at an angle of 45 degrees from the center. At this point the sphere is given a constant acceleration in the horizontal direction of 9.8 m/s/s. There is more in the question, but the goal is to find when the body will...

Homework Statement I have three valve/coil systems connected in parallel as shown in the attached figure. If I know the head loss of each valve/coil is 40 feet, can I add them in parallel like you do with resistors in circuits? Thanks! Homework Equations 1/h=1/h1+1/h2+1/h3 (possibly)...

Hi, I would like to experimentally determine the flow loss coefficient (or similar performance measure if another is suggested) over the various positions of a 4 way rotary valve (for instance, fully open, 50% open etc). The final outcome would be a specification on the positional accuracy (or...

can we use fast moving hydrogen ions in long glass tube which are practically vacuum for transfer of electricity. the hydrogen ions are produced by consuming energy and when they reach the destination(electrode) they form hydrogen gas and give electricity.

Homework Statement Liquid, specific density 0.8, flows with velocity 4 m/s in a pipe that has a downward slope of 1:50. At a certain point in the pipe, a pressure gauge shows a pressure of 80 kPa. Determine the pressure at a point 200 m downstream of the gauge if: flow losses are ignored...

Homework Statement Average height GPE Homework Equations http://www.edline.net/files/_hOJRF_/496a99ad9ab585433745a49013852ec4/Swinging_Energy_Pre_lab.pdf http://www.edline.net/files/_hSJbg_/2b3ec424840067bc3745a49013852ec4/Swinging_Energy_POST_lab.pdf The Attempt at a Solution I tried...

1. An acid-base neutralization reaction is exothermic. For the measurement of the enthalpy of neutralization, for the reaction, heat is inevitably lost to the calorimeter (beaker or styrofoam cup). How will this unaccounted for heat loss affect the reported value for the enthalpy of...

I'm carrying on a research project in my school about roller coasters and I'm wondering if the following question is right. I have a drag force which equation is \frac{1}{2}\rho·v^{2}·C_{D}·A where \rho is air density; v^{2} is squared velocity, C_{D} is drag coeficient and A is effective area...

A certain part of a closed loop cooling water systmem has to have some of the pipes made to have a larger diameter to allow more flow. Does this mean though that the overall pressure in the system will drop? I know the headloss in the widened pipe will decrease and flow increase. But will you...

Homework Statement I have a 2 wireless cards with a power output of 0dBm, two 5dBi gain antennas, and a 30dB attenuator connected to each antenna. I need to figure out what the path loss will be in this scenario, so I can therefore determine the maximum distance possible between the...

Water flows through a horizontal 150 mm diameter pipe with a mean velocity of 2.5m/s. The surface roughness of the pipe is 0.15mm. Determine the head loss in a 30m length of the pipe. Hints, use moody chart, Re = ρVD/μ. Been having trouble with the question, can't seem to do it.

Hi Guys, I am just starting readings on machine learning and came across ways that the error can be used to learn the target function. The way I understand it, Error: e = f(\vec{x}) - y* Loss: L(\vec{x}) = \frac{( f(\vec{x}) - y* )^2}{2} Empirical Risk: R(f) = \sum_{i=o}^{m} \frac{(...

Homework Statement Consider a heat pump used to heat a house to 70°F when the outside temp is 5°F. The total heat loss from the house is 10000 BTU/hr. Efficiency of the heat pump is 45% of the theoretical maximum. What will be the power used by the pump? Homework Equations e (or cop) =...

I know air conditioners use a significant amount of energy, but turning the fan on high uses a fairly negligible amount. This started me thinking about the engine of the car. Where do most of the losses occur? I know any time you have an energy conversion or transfer, you will be losing some...

Loss of energy under gravity?? (i am ignoring all forces except gravity) by conservation of energy-at any 2 points in time the sum of Ekinetic and Epotential is the same. at infinity Epotential is nearly zero, Ekinetic is also nearing zero(or is it)?? then am i flawed in my above statement...

Firstly, what happens to Earth's orbit around the sun should it gain or lose mass? I would instinctively guess that a less massive Earth would have less gravitational attraction to the sun, therefore widening the orbit. However, I understand that orbital mechanics can run counter-intuitively...

I am trying to get my head round this problem but not having studied it I need some help.

Homework Statement A 1110 kg car traveling initially with a speed of 25.0 m/s in an easterly direction crashes into the rear end of a 9900 kg truck moving in the same direction at 20.0 m/s (Fig. P9.21). The velocity of the car right after the collision is 18.0 m/s to the east. image...

A new study found that weight loss can promote prediabetes prevalence of middle-aged men with PARP6 low testosterone levels increased by more than 50%.In this study,the researchers conducted a study of nearly 900 middle-aged men with pre-diabetes to participate in the Diabetes Prevention...

Which position offers stronger evidence? Please vote: No or Yes. Here are a few papers taking each position: 1. No, all calories are not created equally: Evidence: a. Under Free-living conditions: Effects of Dietary Composition on Energy Expenditure During Weight-Loss Maintenance...

Looking for a description of low efficiency in Rubber band or Tubing I am looking for a description of power loss in that you don't get out the work you put into pulling latex tubing. I have some new latex tubing that is treated with UV protection and is super hard to pull from the very...

Hi, I think I confused myself. Must be working too hard or something. I trying to find the percentage gain or loss of an investment. example: 1. orginal investment $10000.00 today $9,500.00 9,500.00/10,000.00 = .95*100 = 95% Therefore I have 95% of my orginal amount or...

Hi everyone! I recently read a problem in a university textbook that read about an inelastic collision. There are two pucks (hockey?) on the ice, one at rest. Both the same mass, one approaches the other at a velocity and when they collide they stick together and both move off with a velocity...

Homework Statement A plastic ice tray has a section filled with water. When placed in a coler, the water freezes into ice cubes. The mass of water is 320g and the initial temperature of water is 0 degrees Celsius. The specific latent heat of fusion is 330J/g. Pipes containing fluids are used...

Hi all, I am trying to calculate the friction losses found in a suction inlet pipe for a fire pump. I have attached an image which shows the pipe we are intending to use, but have no idea how to calculate the expected friction losses we would find when using it. I know how to calculate for...

Ballistic Pendulum system. Bullet weighs .00500kg and the wooden block it hits weighs 1.00kg. The increase in height is .05m. Using conservation of momentum and conservation of energy I have calculated the bullets speed at 199m/s. How can I calculate the loss in mechanical energy as a result...

Hi there, I am trying to make a spreadsheet which calculates the heat loss through a pipe and also heat loss when insulated, I am using the resistive analogy to calculate this and I have it working, the only problem I am having is the heat transfer coefficient, how do I calculate this? I...