What is decreasing: Definition and 205 Discussions

weight of earth? can anyone tell me the weight of earth?

Homework Statement \sum_{n=1}^{\infty} \frac{n^{k-1}}{n^k+c}, where k is a positive integer.Homework Equations The Attempt at a Solution I found that it was discontinuous at x = (-c)^{1/k}; and to determine if the sequence is decreasing, I took the derivative which is--I think--f'(x) =...

Can decreasing acceleration be negative acceleration ?

Homework Statement On what intervals is the function f(x) = x^4 − 4x^3 both decreasing and concave up? x < 0, 2 < x < 3 x < 3 x < 0, x > 2 x > 0, x < -3 2 < x < 3 Homework Equations The Attempt at a Solution I tried to get the derivative of f(x) to make it greater than 0...

I was told that lubricating the interface of a thrust roller and kiln tire with graphite would reduce the thrust load since the source of the load in the traction. I need some help understanding this concept. Thanks.

I was reading a link i found here on physicsforums called "The relativistic rocket". There was lots of calculations of the required fuel for certain distances and such. However, I understand that time→0 when our velocity v→c. And that will mean we travel a larger distance for a shorter...

The problem is in the attached document. Thanks for any suggestions! Lennart

A sequence (an) is recursively defined by a1 = 1 and an+1 =1 /(2+an ) for all n≥1 I'll prove this sequence is convergent by monoton sequence theorem.ı can find ıt is bounded but ı cannot decide it is monoton because when ı write its terms,Its terms are increasing sometimes decreasing...

A sequence (an) is defined recursively by a1 =1 and an+1 = 1/ 2+an for all n is greater than 1 or equal 1. ı'll prove that this sequence is convergent,buy ı cannot decide whethet it is increasing or decreasing .When ı write terms ,some terms increase some terms decrease.

why does the spacing decrease going down the neck of a guitar? using physics concepts how would this be explained? (equations and concepts)

Determine the monotonicity and boundedness of the sequence. 1) 4n/ (4n2 + 1)22) 2n/ 4n + 1Question: I'm having a problem in knowing whether the approach I'm using is providing the right solutions. in 1) I used the an+1/an and tried to compare their ratios. I end up with: 4n+4/ (4n2 + 8n +...

I am required to show that the potential V= -Vo(1+iε) in the schrodinger equation results in stationary waves that represent exponentially decreasing plane waves. I am also required to calculate the absorption co-efficient. My (inept) attempt at a solution; I know that for a comlpex energy...

What is the difference between decreasing acceleration, deceleration and negative acceleration? Most importantly, i want to clarify that acceleration is the rate of change of velocity over time, it Does not necessarily mean that the car velocity is increasing and that a car is speeding up when...

Homework Statement Define a function g on ℝ by f(x)=1/x if x < 0 and f(x)=-x if x≥0. Prove f is strictly decreasing on the intervals (-∞,0) and [0,∞), but that g is not decreasing on ℝ. Homework Equations The Attempt at a Solution I think I understand what I need to show, but I...

Find an $\displaystyle f(x)$ such that $\displaystyle \frac{1}{f(x)}$ is defined for all $\displaystyle x$ and is bounded, but $\displaystyle f(x)$ is decreasing.

im working on a project that is using a parallel capacitor bank made of four 400V 6300uf caps. I am going to use a 120V outlet as the power source and my problem and question are this: as it is, according to pspice, it will take roughly forever for the bank to reach its 400V from the CW...

When a point source emits sound, the sound travels away from the source as a series of wavefronts - all being spherical shells - away from the source right? Now, we say the energy is conserved if we neglect damping forces in the medium, and so the power delivered by the source should be...

Given any irrational number c > 0, prove that there is a strictly decreasing sequence of rational numbers that converges to c.

Homework Statement Calculate the total charge embodied in a solid with charge density that decreases linearly with height from a value of λ at the bottom to 0 at the top. Solve for a rectangular prism and a sphere. Homework Equations ∫∫∫ρdxdydz ∫∫∫pr^2sinθdrdθd∅ The Attempt at a Solution...

Why is the function decreasing the fastest in the direction of the negative of the gradient? Just because it increases the fastest in the direction of the positive of the gradient why does this have to mean it has to decrease the fstest in the negative of the gradient? If you stand facing a...

Homework Statement Multiple Choice If f is a continuous, decreasing function on [0, 10] with a critical point at (4, 2), which of the following statements must be false? E (A) f (10) is an absolute minimum of f on [0, 10]. (B) f (4) is neither a relative maximum nor a relative minimum...

I have a damped forced vibration problem. Most problems I have dealt with have a constant amplitude sinusoidal force such as F_0sin(wt). Let's say you have an applied force that decreases each second at a constant rate over 11 seconds. It looks like this: F=0.5*[(11-t)sin(2*pi*t)+(11-t)]...

I'm working on a problem that has forced vibration. The force, every time it is applied, is less than the previous impact. For clarity, the problem is dealing with a mining skip that is emptying. The inside of the skip is separated in sections using ribs but the top blocks still exert a force on...

I'm working on a problem that has forced vibration. The force, every time it is applied, is less than the previous impact. For clarity, the problem is dealing with a mining skip that is emptying. The inside of the skip is separated in sections using ribs but the top blocks still exert a force on...

Hey all, I have been mulling this around in my head for awhile and cannot make sense logically. In thinking about a sphere falling through some random liquid, how does decreasing the diameter of the sphere affect the rate at which it falls? I am thinking of two formulas and the seem to...

What is the fastest algorithm to find the closest root (such that the function value at that point is positive to an error but never negative, if not exactly zero) for a strictly decreasing function?

Homework Statement This time I'd like someone to verify that my rationale behind the correct answer is accurate... Which of the following will decrease the chance of turbulent blood flow in a vein? A. Narrowing the vein. B. Thinning the blood without changing its density. C...

I have problem to see clearly the case of rotation of a body about a point with decreasing radius.this can be viewed as a body being rotated about a point with the help of a thread which passes through a hole in a disc and the thread is being pulled to apply a tension and gradually to decrease...

Homework Statement Falls resulting in hip fractures are a major cause of injury and even death to the elderly. Typically, the hip’s speed at impact is about 2.0 m/s. If this can be reduced to 1.3 m/s or less, the hip will usually not fracture. One way to do this is by wearing elastic hip...

I have recently been studying the following function for fun (math nerd): f(x) = x^(1/x) where x is an integer greater than 0 I want to prove that the function is decreasing for x > 2. It seems that the straight forward approach to this proof is to use induction. It can easily be shown...

I remember many years ago, as a little kid, I used to watch a hell lot of National Geographic and Animal Planet. Those were some excellent documentaries and watching them was what got me interested in science and especially life sciences. But for the past few years I have been observing a steady...

I'm not sure whether this belongs in this topic or Beyond the Standard Model. I was reading through various articles and threads on this site when I had an epiphany, and now I am curious to see if it could work. The biggest influence on the fate of the universe is its entropy. Because...

Hey all.Could anyone please make this list according to decreasing in job opportunities after PHD, at least up to 5? Full list would be fantastic! 1.Acoustics 2.Astronomy 3.Astrophysics 4.Atomic physics 5.Bio physics 6.Chaos 7.Chemical Physics 8.Computational Physics 9.Cosmology 10.Cryophysics...

Not a homework problem. I was reading this analysis book by Korner and in it there was a question about Bolzano-Weierstrass property in \mathbb{R} . it states \text{Find a sequence} \ x_n \in [0,1], \text{such that given any x} \in [0,1], \text{we can find} \ n_1 < n_2 < ... s.t. \ x_n_j...

Homework Statement P(x) is an increasing function and Q(x) is a decreasing function in interval a ≤x≤b, x is positive. P(x) and Q(x) are located in 1st quadrant. Another function γ(x) satisfies m≤γ(x)≤M. Find the value of m and M if: a. γ(x) = P(x) - Q(x) b. γ(x) = P(x) . Q(x) c. γ(x) =...

I am working on a preload circuit and am having a difficult time with it. The objective is to apply .15A @ 24V when a control signal reaches 7.5V and decrease current in a somewhat linear fashion to 0A when the control signal reaches 10V. I was looking into a voltage controlled resistor...

Homework Statement Consider the following statements S and R S : Both sinx and cosx are decreasing functions in the interval (π/2,π) R : If a differentiable function decreases in an interval (a,b), then its derivative also decreases in (a,b) Which of the following is/are true? a) Both...

Alright, I'm a bit ignorant when it comes to more advanced subjects (well, very ignorant...), but, from my understanding, according to Einstein's theories, a strong gravitational field, perhaps describable as increased Space-Time density, increases the rate of time of an observer and warps...

I understand that as temperature increases the volume of the container will also rise. Due to the particles having more KE and coming in contact with the container walls more frequently and with more force. My question is.. why isn't the inverse true? When you decrease the volume of the...

This is a short conceptual question. If I place a heat sink in a sealed container, and than raise the ambient temperature in the container, will the heat sink absorb the heat with somewhere close to the same efficiency as it would being used in the traditional application (dispersing it's...

Hey all, I'm and Aerospace undergrad at Cal Poly working on my senior project, which has turned out to be more of a EE project than anything else. Anyways, I'm building a capacitor bank for the firing of an electromagnetic rail gun. I'm attempting to make a PFN (pulse forming network)...

Homework Statement An air race pilot with 54 kg makes a vertical loop with 1200 m of radius, in such a way that the airplane's speed decreases at a constant rate. Knowing that the airplane's seat force acting over the pilot is 1680 N at point A and 350 N at point C, determine the airplane's...

If a static charge is placed on an object, and that object begins to move through space, a magnetic field will form around the object (relative to a stationary observer). At the same time, the static field around the object will begin to reduce. The faster the object moves, the stronger the...

Homework Statement Find a > 0 so that the curves y = sin ax and y = cos ax intersect at right angles (let them intersect at (x0, y0)). 2. The attempt at a solution Thinking about the unit circle, if theta equals pi/4, then sin theta and cos theta would intersect at right angles at...

Homework Statement 1. Determine whether the sequence {an} = n+(1/n) is monotonic increasing or monotonic decreasing. Homework Equations The Attempt at a Solution I plugged in some digits and got this a1=2 a2=5/2=2.5 a3=10/3=3.3333333 a4=17/4=4.25 a5=26/5=5.2 I drew the...

Homework Statement Prove that if a > 0, the sequence \frac{a^{n}}{n!} is eventually decreasing for large n. Homework Equations N/A The Attempt at a Solution I know I'm to prove this by finding the index but I'm at a loss on how to find the index on such a sequence as I'm not...

Homework Statement Give an example of a decreasing sequence of closed balls in a complete metric space with empty intersection. Hint 1: use a metric on N topologically equivalent to the discrete metric so that {n≥k} are closed balls. In={n,n+1,n+2,...}. Homework Equations N/A The...

Hi, I am not a mechanical engineer but an aeronautical engineer. Hence I am very poor with Mechanics & request for your help. I am working on design which produces approximately 17,400N-m of Torque at 25RPM. I want to maintain this Torque but increase the RPM to 1500. Is that possible? I...

I have a problem and I do not how to solve the problem. So please write how I should solve the question. A water well has a diameter of 110mm. Water can be pumped from the well into the tank. Every time the pump is started 40 l of water is pumped away. Find how much the water level of the...

Homework Statement f(x) = (3 sin(x))/(2 + cos(x)) let x_0 be a number in (0, (2/3)*pi], and define a sequence recursively by setting x_n+1 = f(x_n) (1) prove that the sequence {x_n} is strictly decreasing sequence in (0, (2/3)*pi] and that lim x_n =0 (2) Find an integer k greater or equal...