Maximum Definition and 1000 Threads

http://en.wikipedia.org/wiki/Heat_engine This is one of those threads where the OP proposed a device which will not work and hopefully by the end understands why. So here's the device... Air enters through a long intake tube. At the end of the tube it enters a combustion chamber where fuel is...

Homework Statement A 7.0kg box moving at 6.0m/s on a horizontal, frictionless surface runs into a light spring of force constant 50N/cm . What is the maximum compression of the spring? Homework Equations K=1/2mv^2 The Attempt at a Solution K=1/2(7.0)(6)^2 = 126N 126N/(50N/cm)...

Homework Statement So for my intro engineering class one homework problem is given as follows. "Considering only aerodynamic drag force, calculate the maximum speed (in mph), that a vehicle would experience with the following specifications." Horsepower = 330 Mass density of fluid = .077...

Homework Statement Assume the ramp and block make the following coefficients of friction: (μs=0.9 μk=0.3) and the 2 kg mass is placed at rest on the ramp and a horizontal force F is also applied. http://img69.imageshack.us/img69/4097/filepq.jpg What is the biggest magnitude force F...

Homework Statement The problem states to find the maximum acceleration and velocity, the accleration and velocity when the displacement (x) is 1.00cm, and the equation of motion as a function of time if the displacement is A (amplitude) at t=0. We're given that the period (T) is 0.500s and...

Homework Statement A horizontal string tied at both ends is vibrating in its fundamental mode. The traveling waves have speed , frequency , amplitude , and wavelength . Calculate the maximum transverse velocity of the point located at lambda/4. Calculate the maximum transverse acceleration...

During winter why not all the water molecules on the water surface that have 4°C go deep under the water?

Homework Statement A circuit is constructed with an AC generator, a resistor, capacitor and inductor as shown. The generator voltage varies in time as ε = Va - Vb = m*sin(ωt), where m = 24.0 V and ω = 187.0 radians/second. At this frequency,the circuit is in resonance with the maximum value...

Hi guys. Please look at the uploaded picture. Normal stress is difined as: σ= P/A. And the Maximum normal stress σ = P/ (b*h/cos(θ)) ?? The right answers should be σAB= 97,7 MPa and σBC = -66,5 MPa. But how do I calculate it? What I have tried: Force AB: 40* sin(60deg) = 34,641 kN...

Homework Statement You need to derive the general maximum height equation for projectile motion. This equation allows you to calculate the maximum height a projectile reaches or could reach during its motion. Like other such equations we derived in this unit, this one is also very short and...

Homework Statement I have a bar, 500mm long (0.05m) 10mm wide (0.01m) and 3mm deep (0.003 m) The bat has a load applied in the centre of 30n I know the maximum yield stress is 150 mpa 150x10^6 How do I calculate the maximum load the bar can take? Homework Equations I used...

Homework Statement Draw the shear and moment diagrams for the loaded beam. Then answer the questions. The distance x is measured from point A to the right. I have attached an image of the problem. Homework Equations The Attempt at a Solution I've managed to answer...

Homework Statement A wire of length L is placed in a magnetic field B,If the current in the wire is I,then maximum magnetic force on the wire is? Homework Equations The Attempt at a Solution Honestly,I have no idea how to do this..(Im in class 9)

I'm trying to solve this problem via Lagrangian mechanics, but I'm having trouble correctly formulating the problem, I'm hoping one of you kindly people can show me where I'm going wrong. A pendulum bob of mass m hangs in the equilibrium position from a light, inextensible string of length l...

I am stuck with considering a problem. I don't even really know where to start so any pointers would be a great help. I am considering a semi-analytic model for some data i have. The situation is looking at how light propogates from a point source in diamond to air. At the surface of the...

Helping a friend out with some physics 1 mid-semester and It's been a little since I have had a physics course... so the question is "If a 30 g bird lands on a slender branch where it oscillates up and down with simple harmonic motion of amplitude 3.00 x 10^-2m and period 1.2 s"... trying...

Polarized light and their disagreements Starting with 2 vertical photons, how can we argue that the maximum number of disagreements and minimum number for +30° and -30° is Nmin(-30°,30°) ≤ N(60°,0°) ≤ Nmax(-30°,30°)? and should we also not rotate the light?

Ok, so I just had a thought. A Planck length is 1.63e-35m Would that mean that the smallest possible wavelenth of light is 1.63e-35m? Giving a frequency of 1.84e+43 Hz, and, of course, an energy of 3e8 J.

Prove that 12x-8-3x^2 can never be greater than 4. How do you prove? Do you find he discriminant? But isn't discriminant for roots only not equations?

New to this and was thinking about extreme cases to help me get my head around how this all works...need help.. Imagine we have an object with mass moving along. Not that this is possible, but what if all other mass in universe was somehow utilized in some nuclear reaction so ALL energy in...

Homework Statement Here is the problem: I have to calculate the maximum stress for A, B and C. Homework Equations I used: σ = y*F*L / 4*I (but I don't think this is right) σ = maximum stress y = Perpendicular distance from to neutral axis F = load L = length of beam I...

Homework Statement I'm doing a physics lab that involves an inverting amplifier. I'm pretty crap when it comes to electronics. I've discovered that the output voltage won't go past 8Vrms. The amplifier is like the one here...

Hello everyone, As you all know, the temperature of a metal increases under electromagnetic radiation. The metal also has a black body radiation which decreases its temperature. There is an equilibrium temperature which is the maximum temperature of the metal under the radiation. I am looking...

Hello, If a climber attached by rope happened to fall what would be the maximum elastic energy stored in the rope? I believe all the potential energy due to altitude would be converted into elastic in the rope (once the elastic energy is maximum and the kinetic energy equals zero), would it...

1.Suppose that X~B(1,∏). We sample n times and find n1 ones and n2=n-n1zeros a) What is ML estimator of ∏? b) What is the ML estimator of ∏ given 1/2≤∏≤1? c) What is the probability ∏ is greater than 1/2? d) Find the Bayesian estimator of ∏ under quadratic loss with this prior 2. The attempt at...

Hey guys. I'm doing some homework for my circuits class and was wondering if anyone could help me with this question. How do I determine the value of ω will the magnitude of H(jω) be maximum?? In my case, the magnitude of the transfer function is (R/L)/ [sqrt((R+RI)/L)2 + ω2)]

Homework Statement When a certain metallic surface is illuminated with electromagnetic radiation of wavelength λ max kinetic energy of photoelectrons is 40.5 eV. On same surface infrared radiation of 3λ, the ma kinetic energy is 5% less than that of incident radiation. Determine the maximum...

Homework Statement Let a,b,c be real numbers such that a+2b+c=4. Then the max value of (ab+bc+ca) is Homework Equations The Attempt at a Solution I am trying to substitute for b into the second expression but that won't give me the answer. Any help would be appreciated.

1. Homework Statement : The expressions you obtained for acceleration and drainage time (equations 3 and 4 in the manual) both contain the following factor or something equivalent: (D/d)^4-1 In the lab, we will be dealing with a bottle with a diameter around 9 cm. A typical diameter of the...

Homework Statement Niobium metal becomes a superconductor when cooled below 9 K. Its superconductivity is destroyed when the magnetic field inside the superconductor exceeds 0.100 T. Determine the maximum current a 3.00-mm-diameter niobium wire can carry and remain fully superconducting, in...

Homework Equations L(x,p) = \prod_{i=1}^npdf l= \sum_{i=1}^nlog(pdf) Then solve \frac{dl}{dp}=0 for p (parameter we are seeking to estimate) The Attempt at a Solution I know how to do this when we are given a pdf, but I'm confused how to do this when we have a sample.

Homework Statement Consider the area bounded between the curves y=3-x^2 and y=-2x. Suppose two vertical lines, one unit apart, intersect the given area. Where should these lines be placed so that they contain a maximum amount of the given area between them? What is this maximum area...

Assuming a mini-universe with the same laws as our current one. A gas within that universe reaches a state of maximum entropy. Would it remain in that state of maximum entropy once it is reached? Maybe the question does not make much sense. In that case, forgive my ignorance. edit: the...

How do you calculate the Maximum Anglular Velocity (and angle at which this occurs) of a connecting rod which uses a slider-mechanism with an offset crank? ω = 300 rpm, 10\pi rad s-1 crank shaft, r = 50mm (0 → A) connection rod, l = 200mm (A → B) When crank angle = 45 degrees, the...

There is a certain equation relating both Mp (max. overshoot) and damping ration. Which is; Mp = e(-ζ*pi)/(1-ζ2)1/2 What I get from that equation is for every system a certain damping ratio will result the system in a certain amount of max. overshoot. That sounds ridiculous, because...

Homework Statement A 0.145-kg baseball is struck by a bat 1.20 m above the ground, popping straight up at 21.8 m/s. (a) What's the ball's kinetic energy when it leaves the bat? (b) How much work is done by gravity once the ball reaches maximum height? (c) Use your answer in part (b) to find...

Question about maximum Kinetic Energy?? KE & Work problem?? A 1.5 kg block is initially at rest on a horizontal frictionless surface when a horizontal force along an x-axis is applied to the block. The force is given by F(x) = (2.5 - x^(2))i N, where x is in meters and the initial position of...

Hi, Below is my attempt at a comparison between the two above-mentioned methods of estimation. Does anything in the table lack in validity and/or accuracy? Should any properties, advantages/disadvantages be eked out? Any suggestions/comments would be most appreciated! MLE...

Homework Statement Why is 'a' not a local maximum? Homework Equations The Attempt at a Solution According to the definition of a local maximum, I have to take an open interval around 'a' so it seems like 'a' is a local maximum. I don't understand why it isn't.

Hi, I'm in the process of building a marble run out of brass wire using 15mm steel ball bearings. For ease of visualisation, it will be similar in principle to this: http://www.youtube.com/watch?v=0FRYX-kcZ9k&feature=relmfu I want to include a "jump" where the marble travels up a ramp at...

Homework Statement Given the max acceleration of a car, 7.6m/s2, calculate the angle of the slope where the cars wheels will spin out. (Fnet=0). Homework Equations Fnet=ma Ffr=μFn The Attempt at a Solution Since I'm not given μ or anything, I think I'll have to figure that...

Homework Statement The mass of a rocket as it burns its fuel is constantly decreasing, while its speed is increasing. We want to know when the momentum is at its maximum. At what fraction of the initial mass is the momentum a maximum? Homework Equations P = mv The Attempt at a...

Homework Statement A mass of m is placed on the end of a rope of length l and swung in a vertical plane. The rope can withstand a maximum tension of P N(Newtons), after which it breaks. What is the maximum uniform speed that the object can be swung at, before the rope breaks? Homework...

Very commonly in thin film articles/journals, I find the full width at half maximum of X-ray rocking curves associated with the quality (order) of the surface. For example, if the same material is grown on two different substrates, A and B, with FWHM values of 0.11° for A and 0.6° for B, why do...

Hello, I have a physics lab tomorrow and have to answer this question to be admitted in. We haven't begun to talk about Pendulums in lecture yet, so I have NO idea where to start. Here's the question: A mass of 40 kg suspended from a 43-cm long light string forms a simple pendulum. The mass...

Homework Statement An overdamped oscillator with natural frequency w and damping coefficient y starts out at a position xo>0. What is the maximum initial speed (directed toward the origin) it can have and not cross the origin? Homework Equations Overdamped Case Equation...

If ψ is normalize-able and a function of nx, ny, nz, is the maximum energy degeneracy 6? I.E. There can be degeneracy at the same Energy with each state taking a different value of n, yet adding up to some (nx^2+ny^2+nz^2)=Same E, due to the linearity of the operators involved. I guess the...

Prove that for $A \in \mathbb{R}^{n\times n} $ ||A||_{\infty} = \text{max}_{i=1,...,n} \sum_{j=1}^n |a_{ij} | I know that $||A||_{\infty} = \text{max} \dfrac{||Ax||_{\infty} }{||x||_{\infty}} $ such that $x \in \mathbb{R}^n$ any hints

Hi everyone! If i know that acceleration is the derivative of the velocity, why when i throw an object in the air when the object reaches the maximum height its velocity is 0 m/s and its acceleration is still -9.8 m/s^2 ? I mean, the derivative of 0 m/s is not -g but still 0. Who can explain...

Homework Statement The spring block system lies on a smooth horizontal surface.The free end of the spring is being pulled towards right with constant speed v_{0}=2m/s.At t=0 sec the spring of constant k=100 N/cm is unstretched and the block has a speed 1m/s to left.Find the maximum...