Increasing Definition and 468 Threads

Hello, I would like to ask a question regarding possible change of orbital conformation of a fullerene particle filled with metal. Is there any basis to the assumption that for if you encase a metal, such as a round nanoparticle of lead cooled to minimal thermodynamical state, just so it fits...

I'm not entirely clear what shunt resistance is, it's fairly hard to find things on google which refer to it in the context of LEDs. So we did an experiment in which we measured the IV characteristics of InAs at different temperatures, and observed the gradients of these graphs (apparently those...

Is it possible to position enough locations around the globe, that rocket thrust on the proper tangential direction might fire simultaneously and cause the Earths rotational speed to increase by some small amount ? What considerations would need to be contemplated as to how this would impact...

I'm using the book of Jerome Keisler: Elementary calculus an infinitesimal approach. I have trouble understanding the proof of the following theorem. I'm not sure what it means. Theorem: "An increasing sequence <Sn> either converges or diverges to infinity." Proof: Let T be the set of all real...

Hi, I am in the process of calibrating our GC and one of the products we expect to find in our experiment is H2O2, but we only have 30% H2O2 in the lab. I can test 5% to 25% by dissolving further in water, so I can get some sort of calibration curve, but I'm stuck at 30%, is there a simple way...

Hi, so whilst doing some reading I came across a section that said the most efficient way to increase your orbital energy when in an elliptical orbit is to fire your 'boosters' at perigee. I understand that the satellite is moving faster, but why should this mean that more energy is imparted to...

how is this true? I get that it's the rate of change of flux, and if you have a graph of flux linkage against time, the gradient with a constant gradient then emf is constant since it IS the gradient... But how? If the flux linkage is increasing, why doesn't the emf?

We have a 'T' bar shaped frame with a pulley wheel at each end then a wire passing across the pulleys with a 10 kg weight attached to each end making each side perfectly balanced. If we were to physically pull down the weight on one side thus upsetting the balance against gravity, could the...

Homework Statement A railroad car moves under a grain elevator at a constant speed of 4.50 m/s. Grain drops into the car at the rate of 420 kg/min. What is the magnitude of the force needed to keep the car moving at constant speed if friction is negligible? Homework Equations U=V+dV-Vrel , U...

So the main reason I'm posting about this problem is that one of the teaching assistants helped me with this problem, but a buddy of mine got something different on part A and part B (Assess). So I wanted to post up here and see what you guys say. 1. Homework Statement The loop in the...

I am currently using the Adafruit Motor Shield in conjunction with an Arduino Motor Shield to control two 7.2V DC Motors. The DC Motors are being powered by a 7.2V, 3000 mAh Nimh battery. When the two DC Motors are being powered in parallel directly by the Nimh battery, they are able to move...

I am not studying physics so I apologies for my limited knowledge in advance. I felt if I increased speed of reps with sub-maximal weights this increase of speed would increase my 1 rep max using n e=mc2. I'm now not sure as this implies I'm using more energy not applying more force or power...

The question is: Which takes place when a catalyst is added to a reaction at equilibrium? A. The point of equilibrium is shifted to the right. B. The point of equilibrium is shifted to the left. C. The forward and reverse reactions rates are increased unequally. D. The forward and reverse...

Assume that ##\{f_n\}## is a sequence of monotonically increasing functions on ##\mathbb{R}## with ## 0\leq f_n(x) \leq 1 \forall x, n##. Show that there is a subsequence ##n_k## and a function ##f(x) = \underset{k\to\infty}{\lim}f_{n_k}(x)## for every ##x\in \mathbb{R}##. (1) Show that some...

Just curious, explanation if youre going to answer please! 2 horizontal disks stacked on one another spinning at constant v, (about a frictionless axis perpendicular to their center), both have mass. Okay, so let's say its possible to instantaneously remove the top disk. So would that make...

Homework Statement A body of mass 35kg moving with velocity Vox=40m/s is subjected to a constant Force of 55N acting in the same direction.How long does it take the speed to increase twice? Homework Equations I would be grateful if anyone could give me hand to solove it after i find the...

Homework Statement A cart roles down the track with an initial velocity vo. Because of falling rain, water starts filling the cart such that its mass increases linearly with time. The rain that has fallen on the track cause the wagon to experience a frictional force characterized with a...

The explanation of a continuous Markov process X(t) defines an indexed collection of sigma algebras by \mathcal{F}_t = \sigma\{ X(s): s < t\} and this collection is said to be increasing with respect to the index t . I'm trying to understand why the notation used for set inclusion is...

Hi, I'm building an experimental set-up for some heat exchanger I'm trying to analyze, I want to maximize the flow through this little piece. I have a stable temperature bath, (see picture) that has an evacuation valve on the bottom. I only took introduction to Fluid Dynamics (found it amazing...

For a spring and mass system, I've learned the resonance frequency of a system increases with decrease in mass. Not sure if this case is also related but when I attach a coin sized metal onto a piezoelectric material of a smaller size, the resonance frequency range actually goes up (from...

why only light has speed of 299792458 m/s. Possibility to increase the speed. With regards Nilesh

Is it possible to create a cantilever beam with constant or increasing stiffness. I've been experimenting with several different shapes and profiles, and have not had any luck. I know that there are shapes with constant stress throughout, but I'm hoping to find a shape with constant or...

Let $\left\{{a}_{n}\right\}$ be a nonnegative, non-increasing sequence and convergence to $a \ge 0$. Can we say that ${a}_{n}\ge a$ for all n $\in \Bbb{N}$ ? Also, if $\left\{{a}_{n}\right\}$ is a nonnegative, decreasing sequence and convergence to $a \ge 0$. Can we say that ${a}_{n}> a$ for...

Can we say non-increasing equivalent to decreasing (For sequence or functions) ? İn some book, I see that...Can you say something ?

I am curious as to whether a nozzle at the end of a pipe that is completely submerged in water and has a pressurized flow being pumped through it in a closed condition can increase the amount of flow and pressure of the water in a pipe fixed to the exit side of that nozzle if the nozzle uses the...

Please can you give definitions of increasing, non-increasing, decreasing and non-decreasing functions ? I found something but there is a lot of differents between these definitions...Can you give these definitions ? Thank you so much, Best wishes :)

Any one knows a simple way to prevent an increasing current from going above a certain value? Current is increasing over time. Only when it reaches a certain value then I would like to stop it from going above and keep it at that Max value . thank you.

Homework Statement If three number are chosen randomly from the set ##{1,3,3^2,...3^n}## without replacement, then the probability that they form an increasing geometric progression is? (a) 3/2n if n is odd (b) 3/2n if n is even (c)3n/2(n² -1) if n is even...

I am interested in calculating the magnetic field around a wire. Using the formula found here http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/magcur.html#c3 I can calculate that B = (μ0*I)/(2*pi*r) Where I equal current in Amperes, and r equals distance from the wire in meters. This gives...

I am trying to solve a problem using Newtonian Mechanics. I was able to solve it using Lagrangian Mechanics, and got the correct answer from the textbook, but when I use Newtonian I get the wrong answer. I want to be able to do it both ways in order to understand/appreciate the difference...

I'm interested in the following inequality (which may or may not be true) Theorem 1: ##( \sum_{i=1}^n \frac{a_i} {n}\ )( \sum_{i=1}^n \frac{1} {b_i}\ ) > \sum_{i=1}^n \frac{a_i} {b_i}\ ## Where ##n ≥ 2, a_1 < a_2 < ... < a_n## and ##b_1 < b_2 < ... < b_n##. My attempt at a proof: 1) When n =...

Homework Statement Hello, I have a problem about Barlow's wheel experiment with several questions. One of them is how to increase the angular velocity for the wheel. I can either: 1. Increase the current 2. Increase the radius 3. Increase the strength of the magnetic field 4. Decrease...

I reference this forum all the time and you guys are always good at breaking down confusing questions so I decided I needed to make an account and get some help with a mental struggle I have been having for quite some time! Two commonly discussed ways of improving a compressor's efficiency in a...

hello In venturi meters, orifice plate meters and generally when there is a neck, constriction at a point in a pipe there is, at that point, a drop in pressure and an increase in velocity, so that the whole energy is preserved (theoretically) my question is, why if we increase the flow rate...

I know to find the time it takes to travel a distance, you divide the distance by the speed.. but what if you have an increasing speed? Say I wanted to travel 5 miles.. and I start off at 0 mph and by the time I reached the 5 mile mark, I would be traveling at 40 mph and there was a steady...

Homework Statement I have always learned (and read) that an increase in the number of bits causes the height of the 'step' on the graph to decrease. I tried to think about it but cannot come up with a proper explanation for this. THe books I read do not explain why? Can someone please explain...

From the equation for Z from this website...

Starting from the FRW metric (for simplicity flat space, radial direction only): $$ds^2=-c^2dt^2+a(t)^2dr^2$$ If we take dt=0 then the proper distance ds(t) between two spatially separated points at cosmological time t is given by: $$ds(t)=a(t)dr$$ Now at the present time t_0 we can define...

Homework Statement A 1.0m long rod of metal has a diameter of 0.75 cm. This metal has a coefficient of linear expansion α = 4.8 × 10−5 1/K , a density of 9.7 × 103 kg/ m3 , and a heat capacity of 390 J/K . How much energy needs to be added as heat to increase the length of the rod by 7.5 × 10−3...

[Note: no template because this post was moved from the QM subforum] I was working on problem #41 and was confused about what the wave function would look like from the time x = 0 to when E=V0. (See image in...

1. Consider free protons following a circular path in a uniform magnetic field with a radius of 1meter . At t=0 , the magnitude of the uniform magnetic field begins to increase at 0.001Tesla/second . Enter the tangential acceleration of the protons in meters/second2 : positive if they speed...

I'm under the impression that if you increase the frequency of a circuit coupled to an antenna, for the same amount of photons emitted, the frequency of those photons will increase therefore having them carry out more energy total, thus increasing the amount of energy required to power the...

Homework Statement A race car going around a flat, unbanked circular track gradually increases speed as it completes one full trip around the track. Which of the following can explain why the car gains speed? (A) Energy stored in the fuel is converted to mechanical energy. (B) A component of...

Area under decay curve exp(-0.6969t/h) where t is the time (with t=0 initially) and h is a constant "half life" is analytically integrable, but what if the half life is increasing with time? I. e. if h(t) = H + at. (Note exp(-0.6969) is not exactly 0.5 but close and easy to remember.) This...

Homework Statement Explain why the number of modes per particle increases with increasing temperature for all gases (except monatomic gases). Homework EquationsThe Attempt at a Solution I am trying to use an energy argument but to be honest, I don't understand the excited state vs rest state...

I tackle the following game analysis: 2 players, two 6-sided dice. Bigger sum of points win. First roller has an advantage, as he wins even if 2nd player's dice sum equals to his. As the game is played with doubling cube (potentially increasing the odds before any roll), I tried to enumerate...

Homework Statement The figure below shows a moving ball, its momentum, and the net force acting on it an instant in time. At this instant, the ball's speed is: 1) not changing [/B] 2) decreasing 3) increasing Homework Equations None. The Attempt at a Solution My guess would be that the...

Homework Statement My question is similar to this one (https://www.physicsforums.com/threads/metric-function-composed-with-concave-function.566338/), I think. I have a concave function f: [0, \infty) \rightarrow [0, \infty) where f(0) = 0, f(x) > 0, x \neq 0 and I need to show that this...

I am working on a problem like this: Suppose ##\mathscr A_1 \subset \mathscr A_2 \subset \ldots## are sigma-algebras consisting of subsets of a set ##X##. Give an example that ##\bigcup_{i=1}^{\infty} \mathscr A_i## is not sigma-algebra. I was told to work along finite sigma-algebras on...

Homework Statement Prove that the X^2 distribution is stochastically increasing in its degrees of freedom; that is if p>q, then for any a, P(X^2_{p} > a) \geq P(X^2_{q} > a), with strict inequality for some a. Homework Equations 1.(n-1)S^2/\sigma^2 \sim X^2_{n-1} 2.The Chi squared(p) pdf is...