Rate Definition and 1000 Threads

Homework Statement When a weak acid HA is titrated 75% of its endpoint, it has a pH of 5.25. Calculate its Ka. Homework Equations Ka = [H+ ][A- ]/[HA] [H+] = 10^-pH The Attempt at a Solution I found [H+ ] from the pH to be 10^-5.25 M. From the dissociation equation of HA, we know there is a...

I am re-piping a oil line use for burning reclaimed oil and currently the oil returns to the tanks to the bottom of the tanks. I want to have them return to the top of the tanks to increase the mixing of the oil. My only problem is that their are two tanks that will fill up by the same oil line...

I hope putting this in the high energy section is the right section (if not, please let me know which would be more appropriate!) I felt this was appropriate since the work I am doing is high energy astrophysics. So I'm doing some research this summer, and my tasks were to take some data...

According to textbook, elementary reactions have an order of reaction equal to the summation of the stoichiometric coefficients. why is this so? And there is another problem, we can balance an equation in different ways and get different stoichiometric coefficient sets, for rates, which set is...

I am an electrical engineering junior and i am helping some freshmen in a project They are supposed to build a racing car They don't want to use servo motors for the turning mechanism. They want to use the same mechanism the Segway uses, turn one wheel faster then the other, so i wanted to know...

Hi i have calculated compressor , combustor , turbine inlet and outlet temperature , pressure so on and my output of gas turbine is 50MW , So for this i want to calculate the mass flow rate of air and fuel in compressor , combustor , turbine . Like m0=?,m1=?fan inlet,m2=? compressor inlet,m3=...

Homework Statement An object is moving around the unit circle with parametric equations x(t)=cos(t), y(t)=sin(t), so it's location at time t is P(t)=(cos(t),sin(t)) . Assume 0 < t < π/2. At a given time t, the tangent line to the unit circle at the position P(t) will determine a right triangle...

So, I'd like to calculate the dose rate to an object, say 1g of quartz (SiO2) placed into a research reactor neutron flux. The average kinetic energy of research reactor neutrons is 2 MeV but individual neutron energies vary dramatically. Say the thermal neutron flux is 1E13 n/cm2/sec and the...

Hi all, so I am working on a presentation. What I have done so far was to calculate the cosmic ray spectrum (so given some data from Voyager 1 and PAMELA, I found the intensity as a function of the energy, in units of m^-2 (sr s MeV)^-1. Given this function, which is essentially J =...

hello! i was provided by the radii from 0 to 5 cm and a parabolic profile is also given .. in numeric form i was asked to calculate the flow rate how to understand it to solve further kindly help ...

Hi guys, First post on this forum. Greetings from the Netherlands :) I am currently in the process of designing a turbine used in locks in several canals. The turbine is powered when the lock chamber is being emptyed during the lockage. The goal is to calculate the water level in the lock...

In the afternoon, Beth read 100 pages at the rate of 60 pages per hour; in the evening, when she was tired , she read another 100 pages at the rate of 40 pages per hour. What was her avg rate of reading for the day? I can't understand why are we not finding avg time? Homework Equations S= v *...

This is my first time tackling this kind of problem. 1. Let $Q$ be the percentage of what he remembers. 2. Let $t$ be the time in weeks. 3. Initial condition 1: $Q=0.95 $ and $t=0$ 5. Initial condition 2: $Q=0.80 $ and $t=1$ Now I'm stuck about finding the rate. From what I understand...

If 18 men or 20 women can do a work in 9 days, in what time can 4 men and 9 men do the same work? My attempt D = days required 4/162 + 9/180 = 1/D D = 13.388 days Is my solution correct? Thanks!

Which option is closest to scientists' current best estimate for the rate at which a supernova explosions occur somewhere in the milky way galaxy? a) once a day b) once a year c) once every hundred years d) once every thousand years From what I have found online, the current estimate is one...

Homework Statement Homework Equations D = rt The Attempt at a Solution I let d to be the total distance d/3a = t1 ----- time taken for 1st part of the trip d/3b = t2 ----- time taken for 2nd part of the trip d/3c = t3 ------ time taken for the whole trip with uniform speed Since t1+t2...

< Mentor Note -- thread moved to HH from the technical physics forums, so no HH Template is shown >[/color] Need a bit of help here: Which has higher rate of evaporation :- Acetone or Petrol?

if 4 men can colour 48 m of cloth in 2 days, in how many days can 6 men colour a 36 m cloth? Can you give me a general method on solving this problem? Thanks!

Among the following compounds I think D compound has more rate of solvolysis in 50% aq.ethanol at 45°C than compound C . Due to more resonance. But the compound C has more rate . Why?

I work in the oil and gas industry and frequently encounter an issue involving isolation valves that do not seal 100%, and that begs me to ask the following question... I often need to isolate particular sections of piping so that a segment can be opened/disassembled for maintenance. When I...

Hello, my first post here. I encounter a situation frequently at work that I'd like help with so here it is... When I isolate a particular section of pipe (by closing valves), I then bleed off the pressure in the isolated section (volume of isolated pipe varies from 3 cubic meters up to about...

I have a DIY project for a lawn sprinkler system but my flow rate is insufficient : if my setup is to work properly, the sprinkler manufacturer suggests a flow rate of 2880 litres per hour at a pressure no less than 2 psi. I measured the flow rate of my current garden faucet, which is connected...

Homework Statement An aluminum rod 0.500 m in length and with a cross-sectional area of 2.60 cm2 is inserted into a thermally insulated vessel containing liquid helium at 4.20 K. The rod is initially at340 K. (Aluminum has thermal conductivity of 3,100 W/m · K at 4.20 K; ignore its temperature...

Hello - I have a question from a CSET practice exam that I'm having trouble understanding the provided answer. Q Two items are dropped simultaneously from a ten-story building. The items are shaped similarly and are relatively the same weight. Which of the following statements is correct...

Let's introduce a time-varying scalar field ρ(x,y,z,t) [charge density] and vector field J(x,y,z,t) [current density] Assuming the system follows Maxwell's equations, what must both fields satisfy such that ##∇⋅(\frac{∂B}{∂t})=0## ?

Question: Estimate the rate of continuous creation required to keep the density of the universe constant at 10-26kg/m3. Express your answer in protons/year/km3. Attempt: Assuming a spherical matter-dominated Friedmann universe, we know from solving the fluid equation that ρ ∝ 1/a3 (where ρ is...

Homework Statement calculate the flow rate at which oil (kinematic viscocity = (10^-6) (m^2) /s ) flow thru a cast iron pipe 100mm diameter and 115 m long under head difference of 5m Homework EquationsThe Attempt at a Solution hf = 32μLV / ρg(D^2) how to get the value of μ( dynamic viscosity)...

Hi, I recently did an experiment whereby we investigated the velocity distribution of air expelled from a round nozzle whose diameter, D, was 30mm. We have been asked to calculate the volume flow rate at distances of 2D, 6D and 10D along the centreline. We found the flow rates to INCREASE...

which has higher failure rate: linear algebra or intro to programming. I understand failure rate might be skewed: math majors, who are gifted and interested in math, are required to take linear algebra but not intro to programming, while CS majors are required to take both. Which class do CS...

Hey, Suppose you have an enclosed vessel that is full of water. You heat it up then you open a valve, and that will create enough thrust for it to act as a rocket. How much energy is needed for a steam rocket to get heated enough to achieve a mass flow rate of 2430 Kg/s. Mass of water= 256...

Homework Statement Suppose you walk into a sauna that has an ambient temperature of 57.0°C. Calculate the rate of heat transfer to you by radiation given your skin temperature is 37.0°C, the emissivity of skin is 0.95, and the surface area of your body is 1.60 m2. I solved this first part and...

Hi Community, I have this tutorial question. When I look at the first question (a) I think it is FALSE as the surface area would not increase at the same rate as the radius. For the second question I am not sure if I am interpreting it correctly. If $$r=\sqrt{\frac{Ct}{4\varPi}+2}$$ where...

Homework Statement A cylinder of radius ##{R}## is partially filled with water. There is an inverted cone of cone angle 90° and base radius ##{\frac{R}{2}}## which is falling in it with a constant speed ##v=30~cm/s##. Find the rate of increase of water level (in ##cm/s##) when half the...

Ok, so I could do an experiment on this first, but I decided to see if anyone knew beforehand. So basically my question is will different properties of the same temperature, exposed to the same temperature, cool/heat at the same rate? For example would a more viscous liquid cool as fast as...

All guys know the importance of cross section. In a sense, it stands for the possibility of a reaction. I am wondering how many barns above could make nuclear reaction rate almost 100%? Generally speaking, the cross section can span a couple of decades order of magnitude, e.g. 10^-10 to 10^6...

Homework Statement the equation of flow aret given is [(pi)((r_o)^4 ) / 8μ ] [-d/ds (ρ +yz ) ] , but the ans that i got is - [(pi)((r_o)^4 ) / 8μ ] [-d/ds (ρ +yz ) ] , what's wrong with my working ? Homework EquationsThe Attempt at a Solution

How would I calculate the rate that water would boil off? I've done a lot of looking into and found an equation but it doesn't seem quite right. What I found states that the KJ/h delivered to the water divided by the latent heat energy gives you the amount of water that will boil off. I tried...

With basic fractions, the limits of 1/x as x approaches infinity or zero is easily determine: For example, \begin{equation} \lim_{x\to\infty} \frac{1}{x} = 0 \end{equation} \begin{equation} \lim_{x\to 0} \frac{1}{x} = \infty \end{equation} But, we with a operation like ##\frac{f(x)}{g(x)}##...

Homework Statement Question: For a fluid flowing within a horizontal tube, if the diameter of the tube narrows, will the fluid's flow rate increase, resulting in increased pressure in the narrowing and explain your reasoning. Homework Equations Volume flow rate = volume/time Volume = Area x...

Hey I am a 15 year old basketball player looking to dunk a basketball on a 10 foot regulation rim. I'm 6'1", 180 lbs, and I can squat 380 lbs full depth. I think the reason I can't jump high is because I have a slow ROFD. Power= Force/Time Power=Force x Speed of Force Application. This is...

Hi everyone! As an experiment I am trying to calculate building my own PWC similar to a jetski assuming it is for sea level use. I really appreciate all detailed answers as I want to understand. The impeller will be installed under rear of craft, engine is mounted on top. Given Information...

Homework Statement " A horizontal water pipe has a radius of 10 cm and a pressure of 8*10^4 Pa at one end. At the other end the radius is 5 cm and the pressure is 6*10^4 Pa. What is the water flow rate through this pipe? Homework Equations P1 + 0.5 * ρ * v1^2 + h1ρg = P2 + 0.5 * ρ * v2^2 +...

Homework Statement I was told that the flow rate in open system at 2 points in the pipe system are not the same, is it true?? Homework EquationsThe Attempt at a Solution

(a) FIGURE 2 shows two cylindrical tanks interconnected with a pipe which has a valve that creates a constant resistance to flow of Rf when fully open. The height of liquid (of density ρ) in the first tank is hin and the second tank hout. The cross-sectional area of the first tank is Ain m^2 and...

Homework Statement The questions is: For many liquids the viscosity is strongly dependent on temperature. Use the table below to estimate the required maximum temperature of crude oil to flow at a rate of 4Kg s-1 through a 0.3 metre diameter pipe whilst maintaining a laminar flow. In the...

Suppose that the relationship between the tax rate t on imported shoes and the total sales S (in millions of dollars) is given by the function below: S(t) = 5 − 9 * sqrt[3]{t} t = ? Find the tax rate t that maximizes revenue for the government. (Round your answer to three decimal places.)...

Hello, I am new in this field, so maybe my questions will be stupid :) sorry for that :) In the company where I work, they measure flow rates of wastewater using Flow meter (Doppler device). The problem is, that the flow rate is very low, so this device is not submerged completely in the...

Homework Statement for part c , why when the vane is moving , the flow rate doesn't change ? ? Homework EquationsThe Attempt at a Solution The flow rate is given by the formula Q=Av , where A = area , v = velocity . IMO , when the velocity of vane change , the flow rate is no longer 0.687kg/s...

Hello there I'm having real difficulty with a problem to do with air cylinders and would really appreciate some help. I'm attempting to replicate the human breathing system in a simplistic form but I'm having trouble calculating the force required to provide the correct airflow rate at the...

I'm studying about accelerating expansion rate. I am reading that the rate of expansion is accelerating. Now the farther objects are from us the faster they are moving away from us due to expansion. Farther and farther, faster and faster. But that would occur even if the expansion rate is...