Maximum Definition and 1000 Threads

Hi guys, I am confused from what I know the max. value of directional derivative at a point is the length of the gradient vector ∇f or grad. f? Why does the answer in my book of a question say that Max. val of Duf = (√3145)/5 when ∇f = (56/5) i- (3/5) j ? Thanks

I was solving this paper, but got stuck on this question, and it's been bugging me endlessly. I don't know what I'm missing. Here's the question: A rod of 20 dia is fixed to the ceiling of a roof on one end. A rotor of 50 kg mass is attached to the free end with bearings. The CG of the rotor...

Hi everyone, I'm a bit confused with this question. An airline demands that all carry-on bags must have length + width + height at most 90cm. What is the maximum volume of a carry-on bag? How do you know this is the maximum? [Note: You can assume that the airline technically mean "all carry...

Homework Statement You want to throw an apple to your buddy on the second floor balcony that is 2.2m above where you release the apple. When you throw the apple with a speed of 14m/s at an angle of 55° above the horizontal, it gets to your buddy who catches it on the way down. Find the maximum...

Homework Statement y=x+z where the pdf of z is exp(-v-2) for v >= 2 and 0 otherwise and x is just an unknown constant what is the MLE of z which maximizes the condition density f_v(y-x)Homework Equations The Attempt at a Solution f_v(y-x) = integral of -2+x to infinity of exp(-y+x-2) dy =...

Just wanted to see if I did this right

Homework Statement Estimate maximum slit width of a double slit. Homework Equations The Attempt at a Solution Letting the slit width be a, The intensity profile of such a system is: I = I_0 sinc^2\left( \frac{Nkasin \theta}{2} \right) cos^2\left( \frac{kd sin\theta}{2}...

A ball of mass 'm' drops from a height 'h'. Which sticks to a massless hanger after striking it .. Neglect overturning. Find out maximum extension in rod, assuming that the rod is massless..

Homework Statement What is the maximum allowable probability of error is a typical digit in order that the (8, 4) Hamming Code can be used with probability .999 that the receiver will not be misled (i.e., 3 or more errors occur) in a single word? Homework Equations...

have two solar cells which I have connected in Parallel to increase the current provided to the system. I want to calculate the maximum Power point tracking for my solar cells. There was no information provided by the seller except the one below. I have attached the open circuit reading of...

Problem: Let $0<a<b$ i)Show that amongst the triangles with base $a$ and perimeter $a+b$, the maximum area is obtained when the other two sides have equal length $b/2$. ii)Using the result (i) or otherwise show that amongst the quadrilateral of given perimeter, the square has maximum area...

Question; A 1 g mass is suspended by a spring and executes simple harmonic motion when released. At time t=0 the displacement is 40 cm and acceleration is -3.6 cm/s^2. What is the spring constant k? What is the maximum velocity of this mass? At what time would the modulus of the maximum velocity...

Homework Statement find time to reach max height max height is 0.870m mass of diver is 70kg makes an angle when diving of 85 degrees Homework Equations Vf=Vi + gt The Attempt at a Solution Vi=0 Vf=gt t=vf/g = 0.870/9.8 not sure if this the right approach

Hello, This might seem like a very basic problem for the most of you but I am a little bit confused as to the problem of maximum and minimum values. For, example I do understand why y = x^2 has no absolute maximum as y-->\infty as x-->\infty... However, in the closed interval, say, [0, 2]...

Homework Statement Here is the problem with the solution: I feel like the solution should be 10.74m. The maximum allowable length should be the lower one. This is because, for example, if we make the column 11m in length. The Pcr in the zy plane would decrease and since we are applying...

Homework Statement Consider the circuit shown in the figure below. Suppose that R = 46Ω and Z=j14Ω. Determine the maximum average power that can be delivered to the load if the load is pure resistance. Note that the voltage source magnitude is given as Vmax, not VRMS Homework Equations j =...

Hi, I am currently revising photoelectric effect, and i have this question: A metal surface at zero potential emits electrons from its surface if light of wavelength of 450 nm is directed at it but not if light of 650nm is used. Explain why photoelectric emission happens with light of...

Consider a density family $f(x,{\mu})=c_{{\mu}}x^{{\mu}-1}\exp(\frac{-(\ln(x))^2)^2}{2}$ , where $c_{{\mu}}=\frac{1}{{\sqrt{2{\pi}}}}\exp(-{\mu}^2/2)$ For a sample $(X_{1},...,X_{n})$ fnd the maximum likelihood estimator and show it is unbiased. You may find the substitution $y=\ln x$ helpful...

Homework Statement A dragstar which weighs 1000kg has a wheelbase 6m long and is assumed to have an unlimited amount of power available to the rear wheels. If the centre of mass of the vehicle is situated 1m forward of and 0.5m above the contact point of the rear wheels and the coefficient of...

Urgent!How to find the point where Maximum Curvature occurs on graph? Homework Statement The graph(2D) is plotted from experimental data, not from a given equation and within certain limit. I want to know the x&y coordinate where the maximum curvature occur via software means, not manually...

I'm just learning this theory and the maths is really trivial but the theory is slightly confusing me. I understand that if we have some function z=f(x,y) and we graph this on a three dimensional set of axis we will have some surface, we can then extend this by creating level curves in the...

Homework Statement A computer scientist has dropped a tiny pizza crumb onto a magnetic disk. Later, when it's turned on, the disk is rotating at 88 revolutions per second about its axis, which is vertical. The coefficients of kinetic and static friction between pizza crumbs and the disk are...

Hi, I am looking to use My/I to find the maximum bending stress for a beam My problem is I don't know how to find the bending moment- the reason why: The beam has more than one point of load, aside from the reaction points. (Pin joint cantilever beam) The sum of all moments equal 0...

Homework Statement Homework Equations The Attempt at a Solution The text in the black box looks wrong to me. The method below is how I would do it. Why is it wrong? $$To\quad maximize\quad power,\quad \overrightarrow { Z_{ L } } =\overrightarrow { { { Z }_{ th } }^{ * } } \\ \\...

Here is my circuit: β=100, VCEsaturation=0.2V, VBE=0.7V, λ->0, VT=26mV After completing DC analysis I got these results : IB=18.05μA, IC=1.805mA, IE=1.823mA, VCE=4.658V>VCEsaturation=0.2V, gm=0.06943, rCE=∞ Ω, rpi=1.44kΩ. After completing AC analysis I got Av=-115.7, Ai=72.23, Rin=1.040kΩ...

Homework Statement complete problem attached Homework Equations The Attempt at a Solution part I in this question was a bit tricky but i managed to solve it , when i read part II i understood nothing , he usually asks about the tangent not the normal , he asks about the point...

Homework Statement For the following circuit, find the values of RL and CL that maximize the power extracted from the generator. https://dl.dropboxusercontent.com/u/15390227/circuit.jpg Homework Equations Z = R + jX XL = jωL XC = 1/jωC The Attempt at a Solution Immediately...

The problem is to find out the maximum angular velocity that the swing carousel can spin at before the chain holding the passenger breaks. The maximum tension that the chain can withstand is known (T). The radius from the centre of the ride to the chain when stationary is known (r). The...

Homework Statement The independent random variables X_1, ..., X_n have the common probability density function f(x|\alpha, \beta)=\frac{\alpha}{\beta^{\alpha}}x^{\alpha-1} for 0\leq x\leq \beta. Find the maximum likelihood estimators of \alpha and \beta. Homework Equations log...

Let $p,\,q,\,r,\,s,\,t$ be positive integers such that $pqrst=p+q+r+s+t$. Find the maximum possible value of max $\{p,\,q,\,r,\,s,\,t\}$.

Hi I attached the file. there are 3 different types of forces applied. and material's yield strength is 55.1 MPa or 8000 psi. I want to find maximum load of box for each types. I don't know which equation I can use. because the box is empty. the dimension of box is width: 70mm, length...

Here find some attached circuit of three phase cabinet which operation voltage is 400V /415V and have operated current 800A, fault current for 1 sec is 46 KA and have incoming and outgoing links with one phase Lighting and socket. I want to know is there some method that one can calculate...

Homework Statement 1. An experiment consists of giving a sequences of patients a risky treatment until two have died, and then recording N, the number who survived. If p is the proportion killed by the treatment, then the distribution of N is: P(N=n)=(n+1)(1-p)n p2 1)Find a general formula...

Reading this wiki article http://en.wikipedia.org/wiki/Atomic_electron_configuration_table I was surprized to see they predicted 172 elements. Now, since the speed of the electron of Hydrogen is vH = 2,18816 (C/137), and since speed in further elements is multiplied by z (number od protons)...

Homework Statement A model rocket is launched with an initial velocity of 55 m/s. Its height as a function of time can be modeled by h(t) = -4.9t2 + 55t. Determine the maximum height reached by the rocket.Homework Equations h(t) = -4.9t2 + 55tThe Attempt at a Solution h'(0) = 55, since h'(t) =...

Does the tangent of a function being at a maximum necessarily mean that the function itself is at a maximum? I am supposed to find whether del is at a maximum at w = (tansig*taneps)^(-1/2) del = arctan(w*(tsig-teps)/(1+(w^2*(tsig*teps)))) tansig and taneps are constants and w is the...

efficiency -- how to get the maximum efficiency in a circuit? Homework Statement I don't quite understand how to get the maximum efficiency in a circuit. Exemple. 4 Volts and 2.0Ω will produce 8 watts with a current of 2.0 amps. 5 Volts and 3.1Ω will produce 8 watts with a current of...

Homework Statement a. Find the Thevenin equivalent circuit across RL. b. What is the value of RL for maximum power? c. Calculate the maximum power that can be transferred to the resistor RL. Homework Equations The Attempt at a Solution a. Rth=2.88 ohm b. RL=2.88 ohm c...

283) you want to build a volume "V" shaped geometric body torque limited cylindrical half-spheres. If the material lower semisphere costs twice as much as the material of the sides, and the material of the upper hemisphere costs three times, calculate the dimensions of the body more economic...

So, I have this question, but I have no idea what constraint is and how to find a constraint for the length, height and width... and if i say the square wastage is x, then the width is 80-x but I don't know what the length would be with respect to x... , and how do we determine the dimensions..?

The difference between BIL rating and Maximum voltage? Like is the BIL voltage the highest it can take in just one instant? how do i know what is the highest continuous voltage a piece of equipment can take? Like for a Cap bank i see a BIL rating but i need to know what's the maximum voltage...

Homework Statement Mass- 0.8 kg Initial Velocity- 3 m/s Spring constant- 500 N/m No friccion Final velocity- 0 Homework Equations What is the maximum compression of the spring? I don't know where or how to start! Please help.

Homework Statement a) What value of the load resistor RL will extract the maximum amount of power from the circuit below? b) How much power will that be? Hint: you need to use both the concepts of Thevenin equivalent circuits and maximum power transfer. Homework Equations The...

Hello, I was wondering, why is it that when calculating the maximum power transfer, the source voltage is the thévenin voltage, and not the actual source? What we call the load is arbitrary, no?

So our teacher explained to us that there is an optimal angle at which a bottle can be rolled down an incline to achieve 'maximum' velocity but I'm not sure how to find the equation to work this out mathematically rather than using just trial and error. I'm pretty sure that it involves...

Homework Statement A particle receives an impulse that lasts 1s, coming from a upwards vertical force. This force is given by the following equation: F = -8t²+8t. What is the maximum height reached by the particle?Homework Equations F = -8t²+8t The Attempt at a Solution \int(-8t²+8t)dt =...

Homework Statement What is the difference between maximum power in load and maximum power by load and circuit? The Attempt at a Solution I know max power in load is when Rth (Thevenin) = RL(load). And the equation to find power in load is (Vth^2)/(4*Rth). Not sure how to find max...

Homework Statement Assuming steady-state sinusoidal ac.A voltage of 240V at 50Hz applied to an inductor yields a current of 4A.Assume negligible resistance.Find inductance, max stored energy. Homework Equations E=0.5Li^2 X=2*pi*f*L The Attempt at a Solution V/I=X Which I...

Kinematics -- projectile motion -- time to maximum height? Homework Statement The nozzle of a fire hose discharges water at a speed of 10 m/s. The nozzle is aimed straight up. How long does it take for a water drop to reach its maximum height? Start with translating the question: vi= 10 m/s...

Homework Statement The maximum tension the string can have without breaking is Tmax. Derive an expression for Vmax, the maximum speed the ball can have at point Q without breaking the string. Homework Equations F=ma Vc=(mv^2)/r T=mg+ma The Attempt at a Solution I thought I could do...