Rate Definition and 1000 Threads

Hi Guys, I'm solving this for almost a week, this is a part of our probset in chemical kinetics: The thermal decomposition of dimethyl ether: CH3OCH3 ---K1--> CH3' + OCH3' CH3' + CH3OCH3 ---K2--> CH4 + CH2OCH3' CH2OCH3' + --k3---> CH3' + HCHO CH3' + CH2OCH3' ---k4--> C2H5OCH3 using steady-state...

Homework Statement Nitric oxide and oxygen gases react to form nitrogen dioxide gas in the reaction 2NO + O2 -> 2NO2 Write a mathematical expression to represent the rate of production of nitrogen dioxide: 4.0x10-3mol/(L*s) Homework Equations r=k[X]m[Y]n The Attempt at a Solution Not...

My textbook says: One of the decays occurs via a ## b \to c ## quark transition and is 'colour-allowed'.(Left of diagram). The other decay has a of ## b \to c ## and is 'colour-suppressed'.(Right of diagram) I'm unsure of what is meant by these terms, it doesn't really explain. I've...

Hello everyone, I'm new to this forum and this is my first post so go easy! I have an engineering problem which I am uncertain as to how to solve. I am trying to design a basic ballast system for pumping seawater. The idea is to use compressed air to evacuate the water through a series of...

Homework Statement Concentration of Hydrochloric Acid (mol/L) 3 2 1.5 1 0.5 Reaction Rate (s/M) 1.333 13.30 38.67 73.00 1466 Homework Equations r=k[H+]m (r is rate in M/s, k is constant, [ ] is concentration, m is order of reaction) The Attempt at a Solution I'm not entirely...

Does the mass flow rate differ depending on whether it's after the feedwater heaters or before the turbines or is it just constant throughout the entire system?

Hey fellas and ladies. So I have an issue. I've been exercising regularly for about 3 months now by doing jogging and brisk walking. Just basic cardio to get my terrible heart into shape. The thing is, I can't jog for very long at all without my heart rate jumping up to 170-180+. I know this...

I was trying to google it, but coudn't find any specific answer. Oxidation of Magnesium, for example, emits a lot of light. Is there a table of reactions by high much light they create ? What chemical reaction emits the highest number of photons per unit per time ? Thank you.

Is there a direct correlation between calorie burn and heart rate? If an athlete and a couch potato each weighed 175 lbs and ran a mile in 10 minutes, would they burn the same amount of calories? I would assume the couch potato would have a much higher heart rate during this event. Does that...

Hello everyone, I am quite new to Fluid dynamics, so I would like to ask for your help. Is it possible to calculate volumetric flow rate from the instantaneous pressure? We need to know the flow rate of the air entering the cylinder in the engine due to the suction pressure. It is required to...

I was doing my homework and really got stuck on one question. Not looking for just an answer as that is useless, I really want to understand how to do this problem as I have no idea how to involve some of the givens. UO_2 is a common fuel for reactors. If the fuel is enriched to 4 atomic percent...

I'm trying to look up sources on the nyquist sampling rate, but I keep finding this small subtle difference between sources, and I am not sure if it is laziness or some subtle point I am missing. Sometimes I see the nyquist rate as Fs>2Fm and sometimes I see it as Fs>=2Fm. So is it the sampling...

Hello! I have a PAL TV, and that means it is best for footage of 25fps and 50fps The TV's refresh rate is 200Hz Well, my questions are: What happens if I play an NTSC file on the TV? (≈30fps), since it doesn't go well with 200Hz much (isn't a multiple)... I thought about how would the TV...

Homework Statement Ina light bulb, billions of electrons flow through the tungsten wire bumping around, causing the filament to glow hot. Hot tungsten evaporates slowly, so its initial thickness profile r(x, t=0) can change over time. Consider a volume V of tungsten, with N bonds total, each...

Is flow rate at inlet of pressure regulator ( not relief valve) equal to flow rate at outlet ?

Hello, I am Primarily a Software Engineer, but have some background knowledge from my A-Level and Uni days. However, I have the following problem. I'd like to find out the rate of change in pressure across a valve. Here are the things I know about the system: Cv at 100% open = 0.004 (I...

Homework Statement R = 4000mi phi = 60 Me = 5.972E24 kg Mm = 5.972E16 kg distance of procession = 100 mi Homework Equations I know the answer is supposed to be ~1010 years. I also know what I am trying to do is have that e3 axis be pointing straight up, then when the mountain is placed on...

Hello guys, I need to calculate the flow rate for the following system. 2 lines of CO2 cyclinders at 60 bar. Each line (1/2'') goes to a 1/2'' PSV valve. Downstream the 2 PSV the line are collected together into 1'' pipe. The two PSV are identical and as per datasheet they have the following...

Homework Statement [/B] My question is regarding Part B of this problem, I have solved it but I'm wondering if there is another way to solve it since it says dtheta/dt and one of the hints I found online suggested that I use the chain rule. Homework Equations Q = mc(deltaT) Q/t = P The...

Hi. First of all, I should mention that I'm quite a novice in both physics and engineering. Let's consider an hourglass (or a silo) that is inclined at a constant angle. I'm unsure of how to calculate the necessary diameter of an orifice for a given mass or volume of granular matter to...

So I have a problem where I'm given the decay rate of a sample which contains Cs137, 10 mCi, and I'm basically given the percentage of radiation detected by the detector. But the wording of the question is: "What count rate would be observed in a perfectly efficient gamma detector" Sounds to...

Sand falls on to horizontal ground at the rate of 9m^3 per minute and forms a heap in the shape of a right circular cone with vertical angle 60^{\circ}. Show that 10 seconds after the sand begins to fall, the rate at which the radius of the base of the pile is increasing is...

Homework Statement The Attempt at a Solution As far as I know those are correct. Could I have some assistance on how to solve for the rate of change? I know the formula is f(b)-f(a)/b-a but not sure how to go about it

Homework Statement http://postimg.org/image/4ctgrkoop/ I don't understand the final bit, for the 'steady rate of heat transfer for the entire fin', how they went from Fourier's Law to that final expression. Homework EquationsThe Attempt at a Solution I think it involves the previous expression...

Assume that I have absolutely no clue to what is the formula used to generate a sequence. How do I know what kind of formula that is? (Exponential / Linear / Polynomial / etc) Also assume that there is only 1 formula that generates the sequence. I have read somewhere before that: f'(x) ~...

I am helping one of my old physics professor and his Phd design a low-atmospheric vacuum chamber and we're looking at different materials to prevent outgassing. However the tank is almost 1m long and all the equipment inside must be taken out and checked after each test. It would be nice if we...

Currently i have a system using bulk argon and i am changing to nitrogen. To trial this i am going to use cylinders of OFN(oxygen free nitrogen). how do i caculate how many cylinders i need based on a flow rate of 16 liters/min. Thanks

The question is: The rate equation for the reaction A2 + B2 -> 2C (all gases) is rate = k[A2]2[B2]. If the gaseous reaction misture is compressed to half its original volume, by what factor will the reaction rate change. Assume temperature is constant. My thoughts are that the reaction rate...

Homework Statement The problem I have is not actually so much a physics problem but more of a logical problem. When we look at rulers and any kind of measuring tools, we start from zero. We count the number of intervals instead of the divisions. Suppose we have a video with 7 frames per...

The fuel pressure load equation for an aircraft in a constant roll maneuver has the term (as a result of the roll maneuver): \frac{\dot{\phi^2}}{2g}R^2 where R - radius from center of fuselage g - gravitational constant \dot{\phi} - roll rate my question is where does the "2" next to the...

Homework Statement The rate constant for the conversion of methyl isonitrile is 5 x 10^-5. A scientist has a container containing this substance with a partial pressure of 100 torr. After 12.8 hours (46,000 seconds), what is the partial pressure of methyl isonitrile gas inside the container...

Homework Statement Homework Equations Rate of change formula: y2-y1/x2-y2 The Attempt at a Solution If this is a rate of change problem so I use the rate of change formula: y2-y1/x2-y2 and since it's from 2 to 4 I think that would be (2,0) (4,0) and thus (0-0)/(4-2) = 0/2 = 0 I don't...

Why in the Law of Mass Action we raise the concentrations of the reactants to the power of their coefficients according to the stoichiometry of the chemical reaction, while the order of the reaction must be determined experimentally ? I may not understand the difference between them.

Homework Statement I am trying to understand how to obtain the estimated detection rate of a WIMP of mass 100~GeV into a Germanium detector of 1kg and detection efficiency of P_{eff}=70 \% . Homework Equations If you have at hand that the cross section is given \sigma = \mu_R G_F^2 (I...

Im having trouble with this problem to do with applictions of calculus. If two resistors with resistances R1 and R2 are connected in parallel, then the total resistance R measured in ohms (Ω), is given by 1R=1R1+1R2. If R1 and R2 are increasing at rates of 0.4Ω/s and 0.6Ω/s respectively, how...

Homework Statement I didn't know if this was considered "advanced" physics, but it's an intermediate classical mechanics course so I'll just post my question here. Basically, if you have a cardioid ##r(\theta)=k(1+\cos(\theta))##, you can show that the ##\dot{\theta}=\frac{v}{\sqrt{2kr}}##...

Hello there, so I have answered my question from fluid systems but the answer doesn't look right ;/ and I have no idea what have I done wrong. Can you please check and correct where it's wrong ? ;) here is the question: A pipe contains a gradually tapering section in which its diameter decreases...

I am confused about the relation of mass flow rate with different mach numbers in a compressible flow. In wikipedia (http://en.wikipedia.org/wiki/Choked_flow), I read the following: "Although the gas velocity reaches a maximum and becomes choked, the mass flow rate is not choked. The mass flow...

Hi, Can anyone explain me that in chemical kinetics, the rate of reaction can be determined by just determining the rate of any reactant of product involved in the reaction, but how? How the rate of change of concentration of just one specie can tell you about the whole reaction? I found the...

Hi, I have a question regarding the flow rate in a pipe. According to the general rule the flow rate is: Q = v * A where Q [m3/s] v [m/s] A [m2] So according to this formula the flow rate depends only on the inner area of the pipe and the velocity of the fluid and does...

Homework Statement Hello, I have really hard time to express the gas law PV=nRT to PQ=ṁRT where Q is volumetric flow rate and ṁ- mass flow rate. Is it possible ? Teacher told me, it is ... Homework EquationsThe Attempt at a Solution

Hi, I'm not sure if I'm posting in the right spot but I'm going to guess this is an easy question for you all. I'm going to give as much detail as I can, maybe too much.. My 2 family house condo has a single 2" or 3" water supply from the street. It is split to supply the first floor and...

Just a general inquiry, and not for any personal gain and or theory, I would like to know if anyone has developed a formula for measuring the vibrational rate of an atom.

Can anybody tell me about the book 'Quantum Physics' by Stephen Gasiorowicz? You can give some comparison with other books such as Griffiths or Shankar's QM book.

Homework Statement At what rate of interest, compounded continuously, will a bank deposit double in value in 8 years? Homework Equations None. The Attempt at a Solution Q0e8r=2Q0 e8r=2 8r=ln(2) r=ln(2)/8 But the answer is (25/2)ln(2)%. How do I get the answer from there?

I'm designing a testing unit where I need to estimate the smallest diameter of a short complex pipe (around 1 meter, three bends and some diameter viariations). Since the pipe is being cooled down in a water bath after production, my idea is to force water with a known pressure in one end of the...

Homework Statement 2 KClO3 (s) + heat --> 2 KCl (s) + 3 O2 (g) If 0.20 g of KClO3 (s) decomposes in 2.8 s, at what rate is oxygen O2 (g) released over this time at SATP? Homework Equations n = PV/RT The Attempt at a Solution Converted KClO3 to mol. .20 x 1 / 122.5495g = 0.001632 mol...

I Think I understand this, but when I look it up, I keep reading about work done and energy used, which puzzles me. The simple way I have always thought about it is, when you expand a gas you also expand the heat it contains, so while it contains the same amount of heat, it's concentration...

Hi, I'm looking at deriving the limits of ##\dot{a}## as ## a-> \infty ## , using the Friedmann equation and conservtion of the ##_{00}## component of the energy momentum tensor for a perfect fluid. Both of these equations respectively are: ## \dot{a^{2}}=\frac{8\pi G}{3} \rho a^{2} + | k |##...

I am interested in mass flow rate in conveyor screw transportation http://www.colormaxsystems.com/wp-content/uploads/2013/11/5-screws-300x222.jpg any recommended book,engineering guides ?