Maximum Definition and 1000 Threads

Homework Statement A V_s=5V source, with Thevenin resistance R_s=1kΩ, drives a certain number h(fanout) gates, each of which is modeled as a C_g=100fF load. The gates are driven simultaneously (i.e., in parallel). You are given: V_OL= 1V, V_OH = 4V. Ignore the wire resistance. What is the...

Just finished an exam. One problem is bothering me and I want to be certain if it's right. Homework Statement What is the maximum velocity of an object dropped from a 20 m cliff? Assume no air friction and gravity is 10 m/s/s. Homework Equations None given, but I assume v=gt is...

Hey In many places on the Internet you can read how the Nyquist frequency must be at least as high as the signals bandwidth in order to properly reconstruct the signal. Isn't this a big misnomer, since it is not the bandwidth, but the highest frequency of the signal that determines the...

Homework Statement A crate of eggs is located on the back of a truck. The truck rounds a circular bend in the road with radius of 35 meters. If the coefficient of static friction between the crate and the truck is 0.6, what is the maximum speed the truck can go without the crate...

Homework Statement A locomotive (6.4 × 10^5 kg) is used to pull two railway cars (Figure 11). Railway car 1 (5.0 × 10^5 kg) is attached to railway car 2 (3.6 × 10^ kg) by a locking mechanism. A railway engineer tests the mechanism and estimates that it can only withstand 2.0 × 10^5 N of...

1. A block of mass 0.247 kg is placed on top of a light, vertical spring of force constant 5 050 N/m and pushed downward so that the spring is compressed by 0.109 m. After the block is released from rest, it travels upward and then leaves the spring. To what maximum height above the point of...

Homework Statement Two vertical forces are applied to a beam of the cross section shown. Determine the maximum tensile and compressive stresses in portion BC of the beam I have attached an image of the question Homework Equations σ = P/A +/- My/Ix Ix = Ix + Ad2 ---> parallel axis theorem...

Homework Statement Hi all, For my CW I have a question on a simple beam, ABCD and its cross-section. Please see attachment for figures The material of the beam is steel, where modulus of elasticity, E = 210 GN/m^2 I have been asked to calculate the principle stresses and the maximum shear...

Hi! What is the limit to how much you can electrically charge two plates? I want to create the maximum possible force between the two plates per kilogram of plate. Say that the plates are separated by a good vacuum, because that is the best insulator, right? The plates are also surrounded...

Homework Statement Atomic sodium is studied by photoelectron spectroscopy. What is the maximum wavelength of the incident radiation that will ionize the most weakly held electrons in sodium and scatter them so that their de Broglie wavelength measures 3.091e-10 m? Homework Equations...

If we are given a metallic conductor in a given Temperature(Room temperature here), Area of cross section A, is there an upper limit to the strength of the current through such a conductor due to the upper limit for drift velocity(v)?? I=nAve e=electron charge n=electron density

Homework Statement In special conditions, it is possible to measure the energy of a gamma ray photon to 1 part in 10^15. For a photon energy of 50 keV, estimate the maximum lifetime that could be determined be a direct measurement of the spread of photon energy. Homework Equations...

Why do gradient show rate of maximum increase not decrease always?

Homework Statement Calculate the Maximum Bending Moment of the bridge section using the values given. Ra = 61837.91667 N Rb = 78304.5833 N (please refer to attached diagram) Homework Equations shear force is = 0 when x = 13.755998 m (I worked this distance and the shear force equation out...

I have taken a time dependent fluorescence series of spectra for an ethylene glycol solution using a 532nm laser as the excitation source. I have attached the spectra to this post. Nothing looks unusual-there is a sharp notch near the 532nm line--this is due to a filter I have used to protect...

a) what is the maximum weight they can move at constant speed? I used 0.42xmg = 6000 x 360 mg = 5142857 N b)what is the maximum speed with which they can move this weight? im thinking power = F / v is used but I keep getting a large number also I've converted hp to watts.

Consider a bungee jumper of mass 65 kg with a 9.00-m cord tied to his ankles. When stretched, this cord may be treated as a spring, of spring constant 150 N/m. Note that the jump-off point is at x=9.00 m, and the origin for the x-coordinate is at the point where the rubber cord becomes taut...

Homework Statement Calculate the maximum bending moment on the bridge section using the values given. (REFER TO DIAGRAM ATTACHED) mass of bridge = 9250 kg mass of car = 2250 kg length of bridge section = 26 m Homework Equations I worked out previously that: Reaction at A = reaction at B =...

Lets say you have a block of iron with a mass "m" exposed to an infinitely strong magnetic field "B." If there was a strong wooden interface preventing this iron block from moving towards the magnetic field source, how can you calculate the force the iron block would exert on the wooden board?

Hi, I am trying to build a conductivity meter as part of a school project (I have to measure the conductivity, among other things, of local water systems). Unfortunately, I cannot buy one for this project, as it should be home-made for these purposes. If I wanted to create a meter that...

Homework Statement Find the largest possible value of \sqrt{(x-20)(y-x)}+\sqrt{(140-y)(20-x)}+\sqrt{(x-y)(y-140)} subject to ##-40≤x≤100## and ##-20≤y≤200##. Homework Equations The Attempt at a Solution Factoring out ##\sqrt{(x-20)(y-x)(140-y)}## the given expression can be...

ladies and gents I have been set a question for homework which is one where if you get one part wrong then the rest of your answers are in correct. It is a 3 questions in one question and i have answered 1 and 2 but can't seem to do part 3 the question is A torque T = 75Nm is applied to...

[b]1. A 2.5GWth nuclear power plant operates at a high temperature of 570°K. In the winter the average low temperature at which it dumps waste heat is 268°K; in the summer it’s 295°K. Determine the thermodynamic efficiency of the plant in each season, and then derive from it the maximum possible...

Fluctuation theorem says that there will be fluctuations in microscopic scale that results local decreases in entropy even in isolated systems. According to the Poincaré recurrence theorem, after sufficiently long time, any finite system can turn into a state which is very close to its initial...

Hello! How do I calculate the maximum possible rotational speed of a thin walled hollow cylinder? In other words, at what rotational speed will it explode due to centripetal force? This picture shows the plane of rotation...

Homework Statement A circuit is constructed with a resistor, two inductors, one capacitor, one battery and a switch as shown. The value of the resistance is R1 = 481 Ω. The values for the inductances are: L1 = 281 mH and L2 = 163 mH. The capacitance is C = 85 μF and the battery voltage is V...

Homework Statement Here is the question along with the solution: Can anyone explain why the terms I circled in red are different? For the first term there is a negative sign but then the second term does not? Why did it disappear?

Let $E\subset\mathbb{R}^n$ and $f: E\rightarrow\mathbb{R}$ be a continuous function. Prove that if $a$ is a local maximum point for $f$, then either $f$ is differentiable at $x = a$ and $Df(a) = 0$ or $f$ is not differentiable at $x = a$. Deduce that if $f$ is differentiable on $E^o$, then a...

Homework Statement I have found the question I am having trouble with here: http://www.chegg.com/homework-help/questions-and-answers/block-mass-m-rest-surface-incline-adistance-h-10cm-base-height-incline-ish-50cm--coefficie-q218123 Homework Equations See below The Attempt at a Solution After...

Homework Statement A car travels around a circular curve on a flat, horizontal road at a radius of 42meters. the maximum frictional force between the tyres and the road is equal to 20% of the weight of the car calculate the maximum speed at which the car can travel around the curve at a...

Homework Statement A supply plane is flying at 60.0m/s at an altitude of 200.0m. What angle of flight will yield the maximum horizontal range for the dropped package? Homework Equations 1/2(g)(t)2. The Attempt at a Solution So far the only equations that i have, but may be wrong...

Homework Statement The 3.8-kg collar is released from rest at A and slides down the inclined fixed rod in the vertical plane. The coefficient of kinetic friction is 0.51. Calculate (a) the velocity v of the collar as it strikes the spring and (b) the maximum deflection x of the spring. I...

Homework Statement https://www.physicsforums.com/attachments/56019 Homework Equations The Attempt at a Solution The net force will be: F=\frac{2*Sin(\alpha)*q1*q}{(d/cos(\alpha))^{2}}=cos(\alpha)^{2}*Sin(\alpha)*qq1/d^{2} Taking the rerivative to find the maximum we...

Homework Statement http://img855.imageshack.us/img855/6951/captureaww.png Homework Equations The Attempt at a Solution Is one allowed to find R_{Th} by simply short circuiting all voltage source and opening all current sources and finding the equivalent resistance while keeping...

1. A hair dryer has a power rating of 1700 W at 110 V rms. Assume the hair dryer circuit contains only resistance. 2. The peak voltage is sqrt2 * rms voltage. 3. I got my esistance of the heating element is 7.12ohm and the rms current drawn by the hair dryer is 15.45A. But I am...

I'll spare you all the details, but suppose for some reason (too complicated to get into here) I needed to design a capacitor with certain fixed parameters and only one adjustable aspect, and I wanted the design to maximize the total charge the device could store. According to my calculations...

Homework Statement The line segment AB lies on a diameter of a circle of radius 1, and the angle BAC is a right angle. Find the greatest possible value of the sum of the lengths of AB and AC. Homework Equations The Attempt at a Solution I have no idea what parameters to use...

A human cannonball was fired from a cannon with a muzzle velocity of 107 km/h. The firing angle was 45 degrees from the horizontal Ive converted 107 km/h to 29.71 m/s 1.How many seconds did it take for the human cannonball to reach maximum height? 2.How high did he rise? h =...

Homework Statement John wants to measure the distance from his home to his office, so he drives to work several times and measures the distance on his car's odometer. Unfortunately, the odometer records distance only to the nearest mile. (Johns odometer changes abruptly from one digit to the...

Homework Statement This isn't homework, but I thought I would post it here as maybe more people would see it, and as I am not an engineer, it requires someone with more experience. The section is effectively an I beam with a hollow u shaped fitting along the top (see my rough sketch). I just...

Hello everybody. I have trouble of proving the theoretical maximum of heat pump Coefficent of Performance. The thing I'm trying to calculate is for heat pump pumping heat from colder reservoir to the hotter reservoir: COP=Qh/W Qh - heat supplied to the hot reservoir(output) W - mechanical...

Homework Statement The linear thermal expansion coefficient of aluminum is 22.2x10-6 m/m K and that of alumina is 5.4x10-6 m/m K. If the criterion for onset of dislocation plasticity is related to thermal mismatch exceeding Burgers vector for aluminum, which is 2.8x10-10 m. What is the...

Homework Statement I want to find the maximum value of x given that the differential equation relating x is: x' = 0.7548 - 599.49x^6 -2.4038x^2 - 0.12236x^1.5 Where x = 0 at t = 0. I have to do this with MATLAB using Euler's Method and here is my code: x = 0 a = 0 % initial t value b = 1000...

Basically I'm trying to find out how to find the maximum distance between two deuterium nuclei in order to overcome the coulomb barrier, causing them to fuse. Thanks

Homework Statement Suppose that two runners run a 100-meter dash, but the first runner reaches maximum speed more quickly than the second runner. Both runners maintain constant speed once they have reached their maximum speed and cross the finish line at the same time. Which runner has the...

Homework Statement A rocket, initially at rest, is fired vertically with an upward aceleration of 10m/s². At an altitude of .50 km, the engine of the rocket cuts off. What is the maximum altitude it achieves?Homework Equations V² = V_o² + 2aΔx t = (V-V_o)/a The Attempt at a Solution Well I...

A uniform simply supported beam, 5 m long and having a cross-section as shown, is to support a load which varies linearly from zero at the left hand support to a magnitude of 20 kN/m at the right hand support. Determine the position and magnitude of the maximum bending stress. ANS : 140 MPa...

(a) The steel cable to the hoist is 15m in length and has a diameter of 25mm. Its steel has a maximum permissible working stress of 200N/mm2 and a Young’s modulus of elasticity of 210,000N/mm2. The maximum load allowed on the hoist is 75kN. Determine the following:- (i) the cross-sectional...

Homework Statement (b) A steel alloy has an ultimate tensile strength of 820MN/m2 and a fatigue endurance limit of 390MN/m2. The steel is used in a fatigue application in which the alternating stress is 0.3 times the mean stress. Using the Goodman method with a factor of safety of 1.5...

Homework Statement The current-voltage characteristic of a photovoltaic energy converter (solar cell) shown in the attached figure can be approximated by: i = I_1(e^{v/V_{TH}} - 1) - I_2 where the first term characterizes the diode in the dark and I2 is a term that depends on light...