Growth Definition and 312 Threads

I'm looking for an additive I can add to latex paint that will prevent mold and mildew from growing on it. Xylenol comes to mind, but I'm not sure. Or maybe a small amount of benzylkonium cloride. It of course has to have low toxicity, yet be effective on mold. This is part of my...

:frown::frown: Homework Statement Suggest reasons for each ofd the following observations: a.When transplanting a small plant from a pot to the garden, it is importanat to dig it up carrfully, leaving the roots in a ball of soil. If this is not done the plant may wilt after it has been...

I'm in Calc II for the summer, but for some reason my teacher gave us a take-home test on exponential growth. She said we could work together and such, but the class didn't have time, so I was wondering if somebody could check it for me. It seems pretty straight to me, but it's a large chunk...

Can anyone tell me how to calculate population growth. my book doesn't tell me how to do that. is the formula rN=dN/dt

Asphalt potholes seem to have a self-fufillment to maximize their size. They tend to start in the most trafficked areas of a road so that avoiding them risks crossing the double yellow line into oncoming cars, or ramming the curb. Striking one increases its width, breadth and depth...

Homework Statement The number of rabbits in a colony is given by N=80e^(0.02t) where t is in days. c) After how many days will there be 500 rabbits? N=500 A=80 k=0.02 t=? Homework Equations (ln being the exponential logarithm) Q=Ae^kt and possibly the conversion formula: ln y =...

The Problem: Consider a species in which no individuals live beyond 3 years. Divide the population into four age groups labelled by n = 0,1,2 and 3. Assume that only the second and third groups can reproduce. For each group n let bn denote the birthrate and d_n the death rate. Find a matrix A...

Is it possible for a human to have an abnormally fast growth of brain size and development leading to a fully grown adult brain before say age 15 or even 10? If so are there cases like this and what happened to them? Is this how child prodigee comes about? Or is child prodigee usually good at a...

hey, I've always wondered this and couldn't find an answer for it: 1) suppose you're a person who works out, and then you stop. how long does it take for your muscles to go "back to normal." and does this deterioration begin as soon as muscle repair after the workout has stopped (24-36 hours...

i was just wondering abt this thing for a while... the total no. of human beings are increasing over the decades...which means some %ge of the Earth's matter is getting converted in the form of humans...suppose if the population goes on increasing, then theoretically there should be only humans...

So I've been given a differential equation that models bacterial growth, p(t), and the concentration of critical substance, q(t), whatever that's suppose to mean. I've solved both of these and found that: q(t) = q_0 e^{vt} Where q0 is the amount critical substance at t=0. v is a constant. I...

The initial mass of a species of fish in a lake is 7 million tonnes. The mass of fish, if left alone, would increase at a rate proportional to the mass, with a proportionality constant of 2/year. However, commercial fishing removes fish mass at a constant rate of 15 million tonnes per year...

I'm a bit confused about exp growth and exp distribution. Suppose I have a branching process situation, where there are n individuals in generation 0, and each individual produces a random number of offspring, according to some distribution (say Poisson), at each generation. Now, then after a...

I need some help with some statistics stuff. Right now I need it to understand one particular discussion in a poker forum, but I also think that this is a good opportunity for me to learn these things better. That's why I'm posting my questions here instead of in the poker forum. Someone...

http://www.fiscalpolicy.org/FPISmallBusinessMinWage.pdf

A common inhabitant of human intestines is the bacterium Escherichia coli. A cell of this bacterium in a nutrient-broth medium divides into two cells every 20 minutes. The initial population of a culture is 90 cells. the question asks to find the relative growth rate, if we measure t in...

the question is how do I solve (1.024)^t=2.857 and find "t" without using logarithms

In 1980, there were about 170 million vehicles (cars and trucks) and about 227 million people in the United States. The number of vehicles has been growing at 4% a year, while the population has been growing at 1% a year. When was there, on average, one vehicle per person? hmm, I think...

im trying to solve a population growth problem. not sure if I am using the right eqn. Please check: Q: if the population doubles in two years, how long does it take to triple? Solution: general equation for population growth: N=No*e^(rt) 1) find unknown constant "r" from given...

\sum_{p\leq N}\frac{1}{p}=\log\log N + A + O(\frac{1}{\log N}) Does it mean that we can simply replace the O part with a function that is a constant times 1/(log N)? What would be the difference between A + O(\frac{1}{\log N}) and O(1)?

Hi, I need a help on an school assignment. I'm suppost to be doing a presentation about the Growth of IT Architecture, managing it, and the kinds of problem it causes. Anyone have any ideas that I can talk about or any resources would be appreciated thanks!

Hi, I don't know what I am doing wrong in this problem: In 1980 the world population was approximately 4.5 billion and in the year 2000 it was approximately 6 billion. Assume that the world population at each time t increases at a rate proprtional to the population at time t. Measure t in...

I am quite sure the first approach is to use partial fractions but I am unclear how to finish this equation 1/P*dP/dt=b+aP

This seem to be a contraversial issue but does lifting weights during the early teenage years or just before puberty like 14, stunt growth? I am talking about often but normal weight training like 1 hour sessions for 5-6 times a week and with relatively normal weights although on the heavy...

Suppose we have an observer at a large distance from the event horizon of a black hole, pouring matter towards the BH at some constant rate of m per second. Will he see the BH's radius increasing at a rate of 2Gm/c^2 per second, or does gravitational time dilation change the apparent growth rate...

I have f(x,y,z)=(x^2)y-x(e^z) and point Po=(2,-1,pi) I need to find a) gradient at point Po ( done) b) Rate of change of f at point Po in the direction of vector u=i-2j+k (it's also done) c) Unit vector in the direction of fastest growth of f at Po. I can't find formulas for a last on...

I understand why base e can be used when the percent growth per annum is 100%, but I don't understand how it can be justified that the growth for numbers other than 1 can be put into the exponent.

Hey, here is a question I couldn't figure out. I think it's actually really easy, but the wording confuses me. A recent survey showed that the population, P, of Victoria is growing at an annual rate of 1.1%. Let P0 represent the population on January 1, 2001 and let t represent the time, in...

Uranium Tiles and tobacco plant growth Someone told me a few years back that tobacco industries have used uranium tiles to help grow tobacco plants. I wasn't sure about this so I decided to throw the topic at my biology professor in case he knew something I didn't. I don't know if this is...

Why does the hair on our bodies (much like the hair on animals) grow to a certain point, then fall out/stop, but the hair on our heads seems to grow indefinately? Do any other wild animals have hair that can grow forever? I'm not only interested in why it grows in physical terms, but...

I know hair grows from skin, and about 0.5-1.5 inchs long. do u no any way to stop hair growning. any way that is not harmfull or has side effects now and forever. -------------------- Ok, truthly, I have lot os hair on my body, and it seems like growing more and more. I just want to waer...

Experiment to show how algal growth effects plants

Hello I am having major difficulties with two Differential equation. 1. If I have the equation P=2000/(1+9e^.06t). where p=population and t=time. How do I work out when the population is growing the fastest? To work this question out do I just make t the subject and diff twice and let it...

Can anyone here explain to me the role of auxin in cell's elongation? :confused: I think it's related to the acid growth hypothesis,but i need the explanation on how this hypothesis works. :rolleyes: thanks a lot for anyone who help :smile: o:)

A work of an spanish applied mathematician, Antonio Brú, has caused a shock here. Spain has a large tradition in the fight against Cancer, and has great sciencists working in this topic. Take a look at this article: http://www.biophysj.org/cgi/content/full/85/5/2948 (The Biophysical...

If you injected human growth hormone, or something like that, into the brain, would it grow

My friend had to do this problem in Calculus BC. I'm no good at calculus, but I decided it was be fun for someone to figure it out for me. A bacteria culture starts with 500 bacteria and grows at a rate proportional to its size. After 3 hours there are 8000 bacteria. (a) Find an expression...

Hi, I have a question regarding natural growth and logistic models. According to my textbook, any exponential equations, P(t) = e^kt can be expressed logistically as P(t) = K/(1 + Ae^-kt) where A = (K-P0)/P0. When I applied this rule to P(t) = e ^0.0015t, and P(t) = 6000 / (1 + 5e^-0.0015t) it...

An embryo can increase its cell number without increasing its overall size.Is this because cell growth is actively inhibited?

Show log n < O(n^epsilon) for n sufficiently large. Not actually calculus, but it has something to do with limits, so there. :smile: Thanks, Mary

A bacteria culture starts with 300 bacteria and grows at a rate proportional to its size. After 3 hours, there are 9000 bacteria A.) Find an expression for the number of bacteria after t hours. for this part, i got 300*e^{1.133732*t} B.) Find the number of bacteria after 4 hours. well...

The population of the wolves influences the change in population of the mooses. When the population of the wolves increase, the mooses' population also increase. From the population growth formula of the wolves delta N/delta t = rN(K-N)/K which factor affects the population of the mooses...

Very interesting about the highly organized distribution of pirated material on the internet. http://www.wired.com/wired/archive/13.01/topsite.html http://www.cnn.com/2005/TECH/internet/01/03/online.underground.ap/index.html It is strange that the FBI have not been able to shut down the...

Hey, I was wondering if sit ups/curl ups and weight lifting stunt growth. Due to the amount of weight and muscle not allowing bones to grow any further. If so, does sitting down while lifting weights help?

Alright, my teacher the sadist gave us an assignment over the holidays, and so far, everyone in my class has gotten all but this. The equation is representative of the population growth of fish in a fish pond. p= m / 1+ae to the -kt p is the intial population, m the carrying capacity...

Hello, my problem is: Let Q(t) = 8(0.87)^t Find the annual and daily growth rate. Can anyone tell me how to set this up? I don't want you to show me the whole problem, just the 1st step. Thanks a ton!

Hi. Just a problem with diauxic growth. If there are glucose and lactose in a medium, the glucose will exhibit catabolic repression, inhibiting the syntheis of lactase. However when glucose is in scarce supply a microogranism will start making lactase. The problem is, when lactase hydrolyses...

can anyone show me how to solve this equation that represents the tumor growth ds/dt = - a s ln(bs) where a and b are constants

Does anyone know how to use the growth and decay functions? How would any of these be useful in everyday life?

Alright problem is pretty simple, I have two functions f(x) = n! g(x) = 2^n Question is to show that g(x) = Of(x) through mathematical expression that is show the growth rate of g(x) <= that of f(x) The fact that this is true is fairly obvious, it's bigger for n>3. Anyway my...