Rate Definition and 1000 Threads

Homework Statement Ship A is 100 km west of ship B. Ship A is moving at 35 km/h (west), ship B is moving at 25 km/h (north). Find the rate of change of the distance between the two ships after 4 hours. Homework Equations The Attempt at a Solution the distance between the two ships is shown by...

Homework Statement A coil has self inductance L of 2 Henrys, and a resistance R of 100 Ohms. A DC supply voltage E of 100 volts is applied to the coil. Show graphically the approximate rate at which the current increases at the moment of switching on (t=0) and after 10ms. Confirm your...

Homework Statement A hot reservoir is maintained at a temperature of 78 oC, and a cold reservoir is maintained at a temperature of 5oC. They are separated by 11.00 cm, and are connected by a cylindrical bar made of two materials. The radius of the bar is 0.83 cm. The upper part of the bar is...

Homework Statement How fast is the volume of a rectangular box changing when the length = 6 cm, width = 5 cm and depth = 4 cm and the length and height are increasing at a rate of 1 cm/s and width is decreasing at a rate of 2 cm/s. Homework Equations Volume of a rectangle = l*w*h The...

Homework Statement Some people are standing at a distance of 3 m from an unshielded 60Co γ-ray source of activity 10^9 Bq. What radiation dose rate are they receiving? (Each disintegration of 60Co produces a β particle of 0.3 MeV maximum energy with a range 0.8 m in air, and two γ rays, one...

Hello Everybody, I'm trying to plot the frequency spectrum of RIN using Matlab. I've the following code function p=rateblock tau_s = 3e-9; N0 = 1e24; A =1e-12; P0 = 1/(A*tau_s); TSPAN = 0:1e-2:10.23;; Y0 =[0 0]; [T,Y] = ODE45(@rate_equation,TSPAN,Y0); subplot(2,1,1)...

Homework Statement i) Estimate (in kg/yr) the rate of Earth accreting inter-planetary dust. Assume a particle number density of n=1e-8/m3, a particle mass density of 5 gm/cc, a particle radius 50 microns and a relative velocity equal to Earth's orbital velocity (so the dust particles are, on...

Hi all, I'm studying Laplace transform right now. And I am trying to understand the s variable in the s-plane. I found online that s = σ + jω where ω is the frequency and σ is the decay rate. Frequency is pretty easy to understand but I can't seem to find anywhere that explains what is the...

The formula f(t) = I(1 + r)t gives the value of something after it has grown for t years, at rate r, with an initial value I. What if the growth rate r is continuously increasing? What is the formula now? Does it relate somehow to xx?

Hi everybody, I am an entry-level engineer working on a launch pad and so far I have little experience with cryogenics. We have a 80,000 gallon capacity liquid oxygen tank on site, and it is generally filled to about 75% full, but varies depending on what is going on. What I am wondering is...

So that's the question and I'm stuck on Part b. I don't even know how to approach it. I know A1= 3A2 but I don't know A1 and I need V2 and I don't know V1 or A2. I'm just confused as to how to do this. Please help!

I'm not sure how to clearly express my query, so I'll round up the gist of it. I understand that this is an entry level question. I was told that, in order to calculate Volume Flow Rate (VFR), I would use these equations: * Q = Velocity * Area [EQUATION 1] * Q = Volume / Time [EQUATION 2]...

Homework Statement If you lie on the ground at night with no cover, you get cold rather quickly. Much of this is due to energy loss by radiation. At night in a dry climate, the temperature of the sky can drop to -40°C. If you are lying on the ground with thin clothing that provides little...

This is the question The flow of a fluid between two large flat parallel plates normal to the y direction is fully developed and steady. The plates are a distance 2h apart in the y direction and the velocity profile, assuming y=0 is at the midpoint between the plate is V(y) = V_0(1-(y/h)^2)...

Homework Statement Find the instantaneous rate of change for the function y2+(xy+1)3=0 at (2,-1) Homework Equations N/A The Attempt at a Solution I tried getting it into a "y=" format but I don't really understand how to deal with the y when it's squared in one part and cubed in...

Homework Statement s(t)= Vit + 1/2 a t^2 + So a) find the average velocity on the interval [1,3] b) find the instantaneous velocity when t= 3s. c) how long does it take the coin to hit the ground? d) find the velocity when the coin hits the ground Homework Equations a= -32ft/(s^2)...

Homework Statement A board 5 feet long slides down a wall. at the instant the bottom end is 4 feet from the wall, the other end is moving down the wall the rate of 2 feet per second.at that moment how fast is the area of the region between the board, the ground and the wall changing...

Hi, I'm designing the attached aquaponic system and am trying to estimate the speed at which water will drain through the pipes. Basically, water enters the top of the pipe, then drains through roughly 5 feet of soil before it exits the pipe. Is there a way to estimate the speed at which the...

Homework Statement A coin is dropped from a height of 800 feet. The height, s(measured in feet), at time, t(measured in seconds is given by: s(t)= Vit + 1/2 a t^2 + So a) find the average velocity on the interval [1,3] b) find the instantaneous velocity when t= 3s. c) how long does it...

Hi, Essentially what I need is a pump that will pump 40 gallons of water per hour to a height of 8 feet. Ignoring pressure losses in the lines (for now) I used the bernouli equation to determine that I need a pressure change of 3.44 psi in my pump. I found these pumps that look suitable but...

Homework Statement Consider energy generation in the Sun. Fusion through the pp cycle takes place within its core which has r = 0.2 Rs T = 1.3 x 10 ^ 7 K rho (density) = 1.1 x 10 ^ 5 kg m^-3 X (total mass fraction of hydrogen) = 0.34 The nuclear energy generation rate for the pp...

I am trying to analyse the relationship of flow rate rate through a simplex nozzle. Here is the situations. Fuel = Kerosene I have a simplex nozzle for injection. And there is a fuel pipe before the nozzle [obviously :P] The flow rate in the pipe is controlled by varying the velocity of fuel...

Homework Statement Air flows through two 8"x10" ducts that merge into a single 18"x14" duct. (Ducts are in 3D) The average speed of air in each of the 8"x10" ducts is 30 ft/s. What is the volume flow rate, of air in the 18"x14" section of the duct? Express the volume flow rate in ft^3/s...

Homework Statement A dish has a shape described by the equation: h=(x^2+y^2)^3/2 At time = 0 it is filled to a height of 20cm with a fluid that evaporates when exposed to air. The evaporation rate is proportional to the exposed surface area (that is decreasing) at any time t. if h(t) is the...

Hey Guys I am making a series of physics tutorials.. with an aim to solve problems and understand concepts without making using of any formulae by making use of animations and some real life examples I started with conceps of relative velocity.. Please tell me if its useful.. I am sorry...

Homework Statement Water flows from a pipe at 650 L/min. a) What is the diameter of the pipe (in cm) of that pipe, if the water flows at 1.5 m/s? Homework Equations Q = V*A Now the equation for the area of a pipe is A = ∏r^2 The Attempt at a Solution Q = 650 L/min V =...

Hi, This is my first post here, but I have searched this forum many times for insight. See the attached image. https://www.physicsforums.com/attachment.php?attachmentid=52558&stc=1&d=1351879807 The red loop is a metalic wire. The wire is expected to corrode when it is submersed into the...

Hello Gentlemen, Do you help me in finding flow rate calculation for diesel engine oil pump? Is anyone know procedure need follow based nominal clearance / maximum clearance? How we can find flow rate requirement for engine.

Hello all! I want to know the difference between growth rate and net growth rate(the context is broad-population or economic,take it as you may).

Homework Statement For a related rate problem I am only given the two rates say dx/dt=1 and dy/dt=2 and a the function which depends on both x and y say f(x,y)=4xy^2 find how it is changing at T=3 Homework Equations Chain rule The Attempt at a Solution So I can take both partial...

Homework Statement The bromination of acetone is catalyzed by acid. CH3COCH3 + Br2 + H2O ------> CH3COCH2 + Br- + H3O+ The rate disappearance of bromine was measured for several different initial concentration of acetone, bromine and hydronium ion as represented in the following table...

So a plane flying horizontally at an altitude of 1 mi and a speed of 50 mi/h passes directly over a radar station. Find the rate at which the distance from the plane to the station is increasing when it is 2 mi away from the station. (Music)

I've read in numerous places that astrophysics/astronomy majors have a 0% unemployment rate e.g. http://graphicsweb.wsj.com/documents/NILF1111/#term= http://finance.yahoo.com/news/4-degrees-with-0--unemployment.html...

So I'm looking through some material on creep for one of my courses. There is a graph of strain ε vs Time, t. Consisting of Primary creep, steady-state creep, and tertiary creep. I pretty much can follow that and understand why the graph looks the way it does. However there is another...

Nitrogen dioxide reacts with carbon monoxide by the overall equation: NO2(g) + CO(g) ----> NO(g)+ CO2(g) At a particular temperature, the reaction is second order In NO2 and zero order in CO. The rate constant is 0.515 L/(mol*s). How much heat energy evolves per second initially from 3.50...

Homework Statement Given the two domains pictured below, calculate the heat transfer rate (Q [W]) for each case. http://img6.imagebanana.com/img/83fe4j54/Selection_001.png The domain on the left is insulated on the left, right, and right half of the bottom side, while the domain on the right...

greetings, how a sampling rate can define bandwidth required for transmission of that signal.if sampling rate is high then bandwidth requirement is also high,how?

Objects burn up entering Earth's atmosphere. If we were to float high enough wouldn't the same thing happen? Or does` the rate of descent play a role?

Hey everyone, So I'm doing a bit of research on transition probabilities for a presentation, and it seems like, from checking different resources, that in the atomic nucleus the process of transition rates to describe the rate of emission/absorption between 2 energy levels is used...

Homework Statement Original function f(x) = -x^2+5x-2 I have calculated the difference quotient as -2x-h+5 Then use difference quotient to calculate the average rate of change: for the following x=2 and x=2+h I need this to go on to the next part of the question and i wanted to ensure...

Rate of change... derivative? Homework Statement the total number of people(in millions) present in a population at a given time is given by the function: 2t(5t+9)^1/2+12 where t represents time (in hours) find the rate in change of the population after 2.5 hours... Homework...

Hi, so I am trying to calculate the maximum height that would be achieved in a cylinder and have been give only the flow rate. The cylinder itself is a simple straight sided cylinder, the opening at the top has a diameter of 5cm and the hole at the bottom has a diameter of 0.5cm...

I'm really not sure, have I gone through the right process here? I didn't actually finish the calculation, I'm just curious about the process.

Homework Statement The oxygen taken in by the body reacts with fats, carbohydrates, and protein, liberating energy internally at a rate of about 2.180×104 J/L. If a 71.40 kg man requires 81.00 W of power even while sleeping, what is his rate of oxygen consumption? Homework Equations p=fv...

1. Water flows out of a cylindrical tank under gravity via a tap, the height h(t) of the water column above the tap satisfies the differential equation in the form dh/dt = -2k√h where k is some positive constant. The water column has a height initially of 25m. The tap is turned on and...

Homework Statement A pump steadily delivers water through a hose terminated by a nozzle. The exit of the nozzle has a diameter of 0.6 cm and is located 10 m above the pump inlet pipe, which has a diameter of 1.2 cm. The pressure is equal to 1 bar at both the inlet and the exit, and the...

Homework Statement Inlet Average Velocity at Inlet = 2.50 m/s Pressure Abs. = 100 Kpa Elev = 2.00 m Inlet tube diameter 12.0 cm Water density 997 kg/m^3 Outlet Average velocity at outlet = 8.00 m/s Elevation = 2.00m a.) Calculate mass flow rate through the pump b.) w/ an outlet pressure of...

Ʃ(\frac{1}{n}) diverges but Ʃ(\frac{1}{n^2}) converges but both corresponding sequences converge (I think). So at what rate does a sequence have to converge for the corresponding series to converge. Or asked differently what is the largest value x can be for Ʃ(\frac{1}{n^x}) to diverge

Homework Statement Captain Ralph is in trouble near the sunny side of Mercury. The temperature of the ship's hull when he is at location (x; y; z) will be given by T=e^(-x²-2y²-3z²). He is currently at (1,1,1). a)In which direction should Ralph go to cool the fastest? b) If the ship can...

Homework Statement The proposed mechanism for a reaction is Cl2 => 2 Cl (Fast) Cl + H2S => HCl + HS (Slow) Cl + HS => HCl + S (Fast) Which of the following would be a rate law for the reaction? The Attempt at a Solution From other questions I've done the rate law for the...