Minimum Definition and 1000 Threads

hi physicists, i have a gnawing question that could be put to rest with experiment but i lack the tools and challenged in ideas. we all know that the speed of light in vacuum is the maximum that can be attained in the universe. also light does not accelerate to that speed, it just begin to exist...

Homework Statement "Calculate the minimum concentrations of formic acid and sodium formate that are needed to prepare 500.0 mL of a pH 3.80 buffer whose pH will not change by more than 0.10 unit if 1.00 mL of 0.100 M strong acid or strong base is added." Ka of formic acid = 1.8E-4 pKa of...

Homework Statement The velocity of a wave of length L in deep water is v = K square root of (L/C + C/L) where K and C are known positive constants. What is the length of the wave that gives the minimum velocity? Homework Equations Possibly a(t) = v'(t) = s"(t) The Attempt at a Solution I...

Just trying to do a problem to find the minimum volume for a homogeneous, bare cylindrical reactor, and my main question is if the radial and axial bucklings are equal to one another at min. V or if there is some other condition that would be helpful. Thanks.

Homework Statement A man at point A on the shore of a circular lake of radius 1mi wants to reach the opposite point C as soon as possible. He can walk 6mi/h and row his boat 3mi/h. At what angle theta to the diameter AC should he row? The Attempt at a Solution My diagram looks like...

I am struggling to find two divergent series, \Sigmaan and \Sigmabn, such that the series of minimum terms, \Sigmamin{an,bn}, actually converges. A further stipulation is that both an and bn must be positive, decreasing sequences. (Otherwise the problem is trivial, as one could simply...

Minimum wattage rating ?? Homework Statement Hi everyone ,, got the following question a. Find the total resistance, current and unknown voltage drops b. Verify KVL around closed loop c. Find the power dissipated by each resistor and note whether the power delivered is equal to the...

Hi experts, :cool: Is it possible to form a h-bridge using 2 spdt relays? What i can find on the net are h-bridges using 4 spst relays or using other types of relays. sincerely Ramone

I have been trying this problem multiple times but it still says I'm wrong: What is the minimum work needed to push a 800 kg car 930 m up along a 9.0^\circ incline? i'm using the formula: W= Fdcos(theta) F= mg what am i doing wrong?

a cannon located 60m from the base of a vertical 25m tall cliff, shoots a 15kg shall at 43 degrees above the horizontal toward the cliff (a) what must the minimum muzzle velocity be for the shell to clear the top of the cliff? (b) the ground at the top of the cliff is level, with a constant...

Homework Statement Hi there Rocket has a total mass of 3.4 x 10^6 kg at lift-off. The first stage contains 2.0 x 10^6 kg of propellants which is consumed at a rate of 1.4 x 10^4 kg s Find the minimum thrust of the engines at lift-off? I would have thought that you needed one more...

Homework Statement Find the value of k if the function y=x^2+kx+72 has a local minimum at x=4

Can anyone provide, or point me to, an explanation of minimum ionizing radiation? My understanding is that in the limit of ultrarelativistic velocities, a charged particle stopping in matter has a dE/dx that approaches some limit. Is this correct, and if so, why does it happen? Is it basically...

Hello all, i am having a few problems simulating cosmic rays with a silicon CCD detector, mainly because my knowledge on particle physics is quite poor. I am simulating primary cosmic rays, which predominantly consist of single protons and alpha particles. I am treating the protons...

I have a Athalon 64 X2 5200+ CPU based system with 2 GB DDR2 RAM & 250 GB Hard Disk . I have a GeForce 8400 GS Card with 512 MB Ram installed in it as well . The Driver version of this card is 6.14.11.8160 as shown by Device Manager . I just read that the minimum requirements for Windows 7 are -...

Homework Statement We have x^2+y^2+z^2=1, and we want to find the maximum and minimum value of xz+xy-yz. Homework Equations The Attempt at a Solution I've simplified the original problem to this point, but I'm not sure what to do next. Could anyone give me some hints? Any help is...

Homework Statement What is the minimum work needed to push a 1770 kg car 346 m up a 16.2 deg incline? Without friction, I got the the answer of 1670000 J. What is the minimum work needed if the coefficient of friction is 0.25? Homework EquationsThe Attempt at a Solution Ff=µFN FN = 17346...

I wanted to know what is the minimum critical mass of natural uranium (99.28% U-238) when moderated by beryllium and light water, when in a optimumally designed lattice. As can be seen in this article (google Plutonium Production Using Natural Uranium) criticality is attained at about 10 tons of...

The problem is regarding two projectiles whose distance of separation is known.Their initial velocities and angle of projection are known, plus these angles are complementary and velocities are known to be equal.It is also known that the two projectiles do no colllide. We are required to find...

Homework Statement There is a hemisphere of radius R metres on the ground. You are standing at the very top of the hemisphere and you kick a ball out such that it travels outwards horizontally with speed v metres per second. During the trajectory of the ball, it does not come into contact...

An alpha particle (made of 2 protons and 2 neutrons) with initial kinetic energy of 1.20 × 10^-12 J travels directly towards the nucleus of the stationary zinc atom The nucleus of a zinc atom contains 30 protons and 35 neutrons, and has a diameter of 4.00 × 10^-13 cm. The alpha particle slows...

Homework Statement a fire hose is turned on the door of a burning building in order to knock the door down. This requires a force a 1000 N. if the hose delivers 40 kg per second, what is the minimum velocity of the stream needed? assuming the water doesn't bounce back? Homework Equations...

Two forces are applied to a 2 kg object floating out in space. One force has a magnitude of 20 N and the other has magnitude of 30 N. Which of the following represent the minimum and maximum of the possible acceleration that the object can have, depending on the relative directions of the two...

[Solved] Two Speakers - Sound Maximum and Sound Minimum Problem Hi, I am having difficulty solving the following problem: Homework Statement Two loudspeakers 5.0 m apart are playing the same frequency. If you stand 13.0 m in front of the plane of the speakers, centered between them, you...

Homework Statement Assume acceleration due to gravity is 9.8ms^-2 It has been said that in his youth George Washington threw a silver dollar across a river. Assuming that the river was 75m wide, (a) what minimum initial speed was necessary to get the coin across the river (b) how long was...

I'm wanting to measure the torque output of a cyclist by measuring the shear force induced in the crank arms. I've done some calculations for the minimum amount of strain that I'll want to pick up and it is around 6e-6 m/m. I'll be using a full wheatstone bridge with a constant voltage...

Homework Statement A plutonium-239 nucleus, initially at rest, undergoes alpha decay to produce a uranium-235 nucleus. The uranium-235 nucleus has a mass of 3.90 x 10-25 kg, and moves away from the location of the decay with a speed of 2.62 x 105 m/s. Determine the minimum electric potential...

I've recently come across a http://technologyinterface.nmsu.edu/Spring08/" for why power is maximised in a component when its resistance R_L equals the internal resistance R. But in part (5) of method 1, we need to find the minimum non-negative value that the expression k+k^-^1 can take. For...

i was thinking,C is the maximum speed something can travel through space,in there a minimum,and is this absoloute zero?

Homework Statement Hello. I am trying to calculate the minimum vacuum force required to keep a climbing robot attached to a ceiling. The robot body consists of a cuboid with two vacuum cups attached at either end. The robot will move using inchworm-style motion, attaching one of the cups...

Homework Statement A truck weighing 3.0 *10^4 Newtons was driven up a hill that is 1.6*10^2 meters long to a level area that is 8.0* 10^2 above the starting point. If the trip look 480 seconds, what was the minimum power required? Homework Equations P= W/t The Attempt at a Solution...

Homework Statement Find the minimum value of arg(z) where z satisfies the inequality |z + 3 -2i| </_ 2 Homework Equations Is this working correct? Thank you for help in advance The Attempt at a Solution Z lies on a circle with radius 2 and centre -3,2 arg(z)min = pi - 2...

Hi What is the minimum mass required to distort space and time ? According to Einstein's General theory of relativity . Mass distorts Space and Time. Well Quantum Physics does not satisfy with General theory of relativity. So, it asks a Question does G exist in quantum size world ? well ...

A 5kg block is placed on top of a 15kg block that rests on a frictionless table. The surface between the top and bottom blocks is roughened so that there is no slipping between the blocks. A 40N horizontal force is applied to the top block. What is the minimum coefficient of static friction...

An atom represents a region about 1.7 10-10 m wide in which an electron is confined. Use the Heisenberg uncertainty principle to estimate the minimum kinetic energy of the electron, expressing your result in electron-volts (eV). So I got the problem right when I analyzed the atom as a 1 d...

Homework Statement The graph below shows all of the quantized energies (bound states) for one of these molecules. For this molecule, E0 = -2.5 eV, E1 = -1.20 eV, E2 = -0.72 eV, and E3 = -0.30 eV. What is the minimum amount of energy required to break a molecule apart, if it is initially in the...

Mass and energy curve spacetime, lots of concentrated mass, lots of curvature. Does the quantized volume of Loop Quantum Gravity correspond to a minimum quantum of energy? If so how does that minimum energy compare to the energy of a individual photon from say a radio station broadcast? It seems...

Homework Statement Consider the function below. (Round the answers to two decimal places. If you need to use - or , enter -INFINITY or INFINITY.) f(θ) = 2cos(θ) + (cos (θ))^2 0 ≤ θ ≤ 2π (a) Find the interval of increase. ( , ) Find the interval of decrease. ( , ) (b) Find the local...

Homework Statement A hydrogen chloride molecule may be modeled as a hydrogen atom (mass: 1.67 x10^-27 kg ) on a spring; the other end of the spring is attached to a rigid wall (the massive chlorine atom). If the minimum photon energy that will promote this molecule to its first excited...

hi, i've read in a lot of places that the minimum speed fora body to "finish" a vertical circle is (rg)^0.5, but I've never understood why.. they assume the if the body passes the top, it will finish the whole circle.. but i can't actually see it... can someone explain/proof it to me? secondly...

Homework Statement The problem is to find the minimum speed of a Formula 1 car that would produce a downforce that is greater than the force of the car. The mass of the car is given: 605kg. Homework Equations I have absolutely no idea what equations to use. The Attempt at a Solution I don't...

What is the minimum potential difference applied to an x-ray tube if x-rays of wavelength 0.250 nm are produced? E=hf f=c/wavelength f=3e8/.250e-9 =1.2e18 then i applied it to the first equation using Plancks constant as h and my final answer came out to be 7.95e-16 KV...

Homework Statement In order to keep a leaking ship from sinking, it is necessary to pump 12.0 of water each second from below deck up a height of 1.50 and over the side. What is the minimum horsepower motor that can be used to save the ship? Homework Equations W=F*d 1 horse...

Ladder Problem :( Homework Statement A 80 kg ladder is 3.00 m in length is placed against the wall ant an unknown angle. The center of gravity of the ladder is 1.2 m from the base of the ladder. The coefficient of friction between the base and the ladder is 0.400. No friction between the...

Finding minimum angular speed?? in rpms In an old-fashioned amusement park ride, passengers stand inside a 5.5-m-diameter hollow steel cylinder with their backs against the wall. The cylinder begins to rotate about a vertical axis. Then the floor on which the passengers are standing suddenly...

Homework Statement Find the absolute max and min of f(t)=t + cot(t/2) on [pi/4, 7pi/4] Homework Equations The Attempt at a Solution I have attempted to find the derivative which I believe is 1 - csc^2 (t/2) * (t/2) which I can simplify down to cot^2 (t/2) * (t/2) Even...

Homework Statement A particle of mass m moves under action of a repulsive central force Fr=Cr-3 with constant C greater than 0. At a very large distance from the centre of the force, the partcle has kinetic energy K and its impact parameter is b. Use conservation of energy and angular...

Homework Statement The potential difference \Delta\phi between the plates of a spherical capacitor is kept constant. Show that then the Electric Field at the surface of the inner sphere will be a minimum if a = \frac{1}{2}b Homework Equations E = \frac{Q}{4\pi\epsilon_{0}r^{2}} between the...

Hello, Let's say I have 500 boxes and 500 hundred non-identical items. I would like to have sets of 40, chosen among those 500 hundred items and my objective is to keep the number of same items in any 2 boxes at a minimum. 1. What would be that minimum number of common items? 2. If...

Homework Statement A roller coaster goes around a vertical loop of 20.0m. a) What is the minimum speed the cars must be moving so that the passengers do not fall out at the top? b) Assuming that the car maintains the same constant speed what is th effective weight of the passengers at the...