Rate Definition and 1000 Threads

I am currently designing a lubrication system which uses a positive displacement gear pump. So how can I get the flow rate of a lubrication system? i don't know which equation to use. thank you so much.

Hello everyone, i am currently dimensioning a compression system using a vehicle turbocharger and need to find a way to relate the pressure ratio of the compressor and the mass flow rate. (flows trough compressor and turbine are of course separated) For the turbine, one can use Stodola's...

< Mentor Note -- thread moved to HH from the technical forums, so no HH Template is shown >[/color] experiment for testing type of catalyst on reaction rate? I need an experiment (just the method) Where I can test the reaction rate of changing the catalyst type I need about 3 differnet...

Homework Statement If an investment increased by 40% over 3 years and rose by the same percentage rate each of those years, what was the rate? Homework Equations new_value = old_value(1+r)^p The Attempt at a Solution Let value of the investment be 1000, then we have 1000(1+0.4) = 1000(1+r)^3...

The social sciences used to have their own forums in PF, what happened to them? They used to be a great lace for discussion. Anyways, this still seems the best place to ask this question. According to Wikipedia at least, the homicide rate in the U.S. per 100,000 persons increased from about...

Homework Statement With the drying out of Central California with global warming, the lapse rate may change from a moist adiabatic lapse rate to a dry lapse rate. Does this mean the lapse rate would decrease or increase? Homework Equations...

1. Homework Statement Given the following diagram of a finite potential well, calculate the rate at which the right-going wave is bringing probability density up to the barrier. (Ignore interference with the left-going wave. ) (Hint: you can get the velocity from the energy, and the average...

Assuming that your surface temperature is 99.1 F and that you are an ideal blackbody radiator (you are close), find (a) the wavelength at which your spectral radiancy is maximum,(b) the power at which you emit thermal radiation in a wavelength range of 1.0 nm at that wavelength, from a surface...

I've always been taught that in a piping system (only water), if the flow rate doubles, then pressure loss quadruples. But when using the Darcy-Weisbach equation I often find that it is closer to triple. Playing around with viscosity and temperature I've never been able to bring the ratio higher...

Hi, I used a blower to flow air across an open duct through a nozzle. By using a gate valve, the mass flow rates were controlled. I took measurement in 3 different locations along the ducts. But, why by decreasing the mass flow rate, the air velocity was increased? It is just happened for the...

Homework Statement A tank of cross-sectional area A is initially filled with fluid of density ρ and viscosity μ to height hi. The pressure above the fluid in the tank is atmospheric, Patm. At the base of the tank there are two pipes, which are both open to teh atmosphere, such that fluid...

The temperature at a point (x, y) on a flat metal plate is given by T(x, y) = 62/(9 + x2 + y2) where T is measured in °C and x, y in meters. Find the rate of change of temperature with respect to distance at the point (1, 1) in the x-direction and the y-direction. My solution so far: dT/dx...

Homework Statement A thin ring (radius r = 1.41 cm) carries a charge Q = 8.57 pC distributed uniformly along its length. The ring lies in the y-z plane, so the axis through its center is the x-axis . A small detector is moving along the positive x-axis toward the ring at velocity v = -0.543i...

Please help me on this... The following circuit is of an active rectifier..The inclusion of a diode here signifies a voltage follower for positive Vin voltages ...but for negative Vin diode is off hence the out voltage Vout is zero...and the output of the opamp goes into negative saturation...

Hi , Can we replace battery with capacitor?? I know that energy stored in a battery is far greater than in the capacitors ,but still can we some how convert a charged capacitor into a temporary battery?? So the Question is how to control the discharge rate of capacitor? Is this have something...

First post on these forums, thanks all for your help! Homework Statement It is estimated that the growth rate of the fin whale population (per year) is rx(1 - x/K), where r = 0.08 is the intrinsic growth rate, K = 400,000 is the maximum sustainable population, and x is the current population...

Homework Statement A football player releases a ball at 35° with initial velocity of 80 ft/sec. Determine the radius of curvature of the trajectory at times t = 1 sec and t = 2 sec, where t = 0 is the time of release from the quarterback's hand. For each case, compute the time rate of change...

So this is my first question here, and I hope I'm doing it right! My question is basically this: Find the average rate of change of the function from x1 to x2. f(x) = x^2 + 12x -4 I'm also new to precalc, so please don't blame me if this is a really easy question! It doesn't seem to make...

Well,I know that the activation energy of a parallel reaction can be determined by the arrhenius equation as (e1k1+e2k2)/(k1+k2) where e1,k1 and e2,k2 are the activation energies and rate constants for the two reacations.now consider the reaction A》B,and A》C since at every instant the reacted...

So in many books, authors state that the supply rate, u^3/l is proportional to the dissipation rate ɛ, in a turbulent flow i.e: u^3/l ~ ɛ where u and l are characteristic velocity and length scales of the large eddies. Many will also state that the small scale eddies have a time period or...

I am reading gravitation and spacetime by Hans Ohanian and he is discussing the possibility of the constants, such as proton mass, fine structure constant, etc, actually changing over time. He makes the claim that since the universe is ~10^10 years old the expected change should be...

Hi everyone, I am an electrical engineering student and in my free time, I make educational youtube videos about electronics. (youtube.com/SolidStateWorkshop). I'm working on a video right now about transistors. To help explain their operation, I am attempting to use a hydraulic circuit...

Hi all, I would like to estimate from my experimental data what would be the noise of the signal if I could sample at a higher rate. It is possible to do that? Do you have any references to good books that explain this topic? Thank you!

I'd like to find out how other members usually think of the Hubble rate, by preference and/or by habit. I was unsuccessful in creating a poll in Cosmology (no "add a poll" button) so I'm hoping this thread can be moved over there. Here are the options I could think of: 1. As a continuously...

If I imagine an interplanetary fight between two early races (the universe is about 8 billion years old) and one of them invents a super weapon to extinct the other. The weapon is a grey goo weapon, a swarm of billions of machines, each with the ability to bend light around it to cloak itself...

Okay, so this is my first post, and I'm probably going to embarrass myself, but here goes. I have a bunch of questions. So we have an atom, consisting of a proton and electrons, and these electrons spin either clock wise or anti clock wise but in fact appear to do both... until measured...Is...

Homework Statement A patient, on an anesthetic, is hooked up with only 18 mg of the anesthetic remaining. If the current flow is 12 mg/h and the dentist needs to increase the flow to 20.0 mg/h within two minutes, then how long will it take for the anesthetic to run out? Homework Equations...

Hello, recently I became interested in some basics of material science and there was one thing that I did not really understand. What is the difference (or what are things in common) between creep and strain rate sensitivity? I read about it in connection with indentation. - To measure the...

I know that F=ma which give the units of kg.m/s/s (in SI units) but can force also be expressed as mass flow rate times velocity which also has the same units? Example: water coming out a hose or gas coming out a spray can?

< Mentor Note -- thread moved to HH from the technical forums, so no HH Template is shown >[/color] The max flow rate through a control valve with an equal percentage characteristic is 10 m3/h. If the valve has a rangeability ratio of 50:1 and is subjected to a constant differential pressure...

Homework Statement A spectator is standing 50 ft from the freight elevator shaft of a building which is under construction. The elevator is ascending at a constant rate of 20 ft/sec. How fast is the angle of elevation of the spectator's line of sight to the elevator increasing when the elevator...

if acceleration is defined as rate of change in velocity, then how do you find out the unit of rate of change of acceleration?

Batteries and rate of charge? I have an IPad. It 'seems' that when he battery if fully or mostly charged it lasts proportionately longer than when less charged. For instance, all things equal, the battery takes a shorter time to drain from 30% charged to 10% than it does from 90% to 70%...

Homework Statement I have a homework assignment that I find challengingA spherical baloon is being inflated at a rate of 10 cu.in/sec (i assume it's cubic inches per second) Find the rate of change of area when the baloon has radius=6Homework Equations So far I know that V=(4/3)*pi*r^3...

Let's say I have a shell and tube heat exchanger that is producing steam. I have a known volume of water entering the shell of the heat exchanger. Would the rate of steam generation be something like... rate of steam generation = (volume of water)*(density of steam)/(time it takes to deplete...

So we all know that due to the conservation of volume flow rate, reducing the diameter of a hose pipe would increase the velocity of the water flow.(A*V is conserved) But when the are of an orifice near the bottom of a water tank is reduced the velocity remains the same! Does anyone know why...

Time can have 2 different connotations. One is inherent to an entity in spacetime by itself, say a lonely radioactive atom. It may decay or it may not decay, independently of what's going on around it. But another involves interactions between particles, for example "it takes 60 seconds for...

Hello! I've been researching hygroscopic materials and evaporation rate a bit lately, and a question has struck me which I haven't found an answer to yet: What material factors affect the rate of evaporation? Is it possible to engineer a material which is hygroscopic (absorbs water) in humid...

Hi there guys, I'm conducting an experiment to calculate the mass flow rate of water. Bellow is a copy of the procedure: 1) Weigh the mass in kg of a container 2) Connect a flow meter to a tap (any source) with a pipe and insure the departure pipe goes into a sink 3) Open the tap an increase...

Hi guys, quick simple question. Lets say I have a pipe separated into 3 sectoins (all horizontal), all have the same flow areas. In the first section it is all liquid water. I know the mass flow rate in this. In the second section the water is heated. And I can work out the steam quality...

Hi, If I'm moving away from a light source flashing light, according to Doppler effect I would have more time between flashes from my perspective than a still observer from perspective of the source, my explanation would be that the source really waits this exact time, and I can relate it to a...

I'm redesigning a small, U-shaped spring clip, similar in shape to this: To make it fit, I had to increase the radii in the corners from the original design, so I need to validate that it will still have sufficient spring rate/clamp force for our application. I'm trying to figure out how I...

So say I have a tank of water of about 2000mls which is at around 80 degrees celsius and is pumped around a copper system which is 3/8th inch thick pipe. how many meters would the water have to travel through copper pipe to return to ambient room temperature of about 20 degrees celsius. any help...

If you use Newtons gravity equation; F=M1*M2/d^2. The force is dependent on the mass of two bodies so how could the mass cancel? Also, for example If I had a bowling ball and a ball the mass of the sun and droped them 100 feet above Earth The two balls would not accelerate at the same rate...

Homework Statement A reactor fires out ##10^{21}## neutrinos per second. A detector containing ##10m^3## of liquid which contains 30 carbon atoms every 60 hydrogen atoms. The detector-reactor distance is ##1000##. The cross section for the reaction is ##\sigma = 10^{-46} m^2##, and the density...

As we get closer to the Earth's center, clocks down there tick slower that ours in the surface. Does this have any noticeable effects? Just for example, could we notice that certain reactions such as radioactive decay happen 'too slow' down there compared to what we know as the normal rate in...

Is it true that the universe itself expands faster than c = 3 × 10^8 m/s at some places / areas / points. I have heard it but wasn't able to confirm. Because outside of the the universe, there ain't anything as far as we understand and hence the universe should not have to follow any law as...

Hello, I have another crazy project I'm working on and I need to know if this is viable before I spend a bunch of time and money. Here is the situation: I have a small block of Al. 1/4" x 1/4" x 1" long. Thru the length I drill a 1/16" hole. The surface will be whatever a standard drill bit...

My question is pressure a rate? Rate is defined as a some measure per another measure or quantity. Doesn't pressure fit that definition? yet everything I read says no...pressure is not a rate? Same with density Is it because pressure is really a distributed force per area, and it is not a value...

Homework Statement I am trying to figure out how to calculate the rate at which a piece of carpet can absorb a liquid such as water or oil. This is for a real life project. I thought that maybe I could use related rates to solve for the rate of volume increase in the carpet if it was...