Metal Definition and 999 Threads

I was at a home today which a while back had a lightning bolt strike the chimney and explode the top of the chimney off. On the drive home I got to thinking, I have two metal chimney liners, one for a first floor wood-stove and another for the furnace and only the furnace liner is indirectly...

let's say we have a square piece of metal and we put this piece in a variable magnetic field, would it get heated? is this the idea of a current? If we have a rotating metal disk (as the case of a saw for instance), and then we put this rotating disk in a constant uniform magnetic field such...

For instance, let's say that i have a piece of metal (ie paperclip, coin, etc) that sticks to a magnet. Is there a way to remove its magnetic properties, so that it can't stick to metal? Using curie point to demagnetize is only temporary. Is there a way to permanently demagnitize a magnetic...

let's say we have a square piece of metal and we put this piece in a variable magnetic field, would it get heated? is this the idea of a current? If we have a rotating metal disk (as the case of a saw for instance), and the we put this rotating disk in a constant uniform magnetic field such...

Homework Statement A slab made of unknown material is connected to a power supply as shown in the figure. There is a uniform magnetic field of 0.5 tesla pointing upward throughout this region (perpendicular to the horizontal slab). Two voltmeters are connected to the slab and read steady...

Hello Experts, I am a novice trying to make a small atenna for GSM signals. I tried using insulated iron wire. Its my 1st time experimenting with antennas. My question is how does the type of metal used affect an antenna? For example, some use copper wire. Will it have a better...

I think the broadest way to frame this question would be as follows: "If a metal conductor (copper wire) were bent at room temperature, then placed in a cryo-cooler and cooled to ~30-80 kelvin, would it experience any 'unbending?'" More specific to the situation, I've bent down the center...

Homework Statement Calculate the surface charge distribution on a metal disc of radius R having total charge +q. Homework Equations The Attempt at a Solution

Hi, again very simple problem Homework Statement Metal sphere of radius R1 is charged to 10V. It is then connected to another sphere with R2 = 2*R1. What is the final potential? Homework Equations The Attempt at a Solution V = E * distance so in the case of disconnected...

Hi, ***I just noticed this that I posted this in the wrong section thinking I was in the engineering forum...sorry!*** I'm designing a racking system to store sheet metal coils (see attached sketch). I calculated the I and S values required and according to my calculations, 4 x 4 x 3/8...

Hi all, This is about installing UV lamps so I guess I should post this in the Electrical sub-forum. I am actually looking for a short but power UV lamps with the purpose of polymerization of chemical monomer. My original search parameter of lamps: -Able to hit up to 25mW/cm2. -Total...

What an Atom in say a lump of steel in melted to molten metal, what happens to the Atoms ? Surely they melt and are destroyed, or do they reform ? As I thought everything was made of Atoms ? Are water and such made of Atoms ? Wayne

Homework Statement The field just outside a 3.22 cm radius metal ball is 2.72×10^2N/C and points toward the ball. What charge resides on the ball? Homework Equations E = k*q/r^2 The Attempt at a Solution q = E*r^2/k q = ( 2.72*10^2 N/C )* (0.0322 m^2) / 8.99*10^9 =...

We are demolishing some old cryogenic tanks and inside them were large metal balls. The metal is very hard and dense and has a yellowish tint. The tanks are large upright and cylindrical. Need information on the purpose of the balls and what material(s) they might be made of. I would...

Hi everyone, I recently started studying heat conduction using differential equations and this has been stumping me for a while. I am having trouble understanding what type of heat conduction problem this is. We are given a 100cm long copper rod with ends maintained at 0 C. The center of the...

Homework Statement A square metal plate 0.180m on each side is pivoted about an axis through point O at its center and perpendicular to the plate. Calculate the net torque about this axis due to the three forces shown in the figure if the magnitudes of the forces are F1 = 18.0 N, F2 = 17.0 N...

what are the different types of methods to make a metal positively charged?

Homework Statement Explain the factors that determine the parallel and normal components of the elctric field near to the surface of a flat metal plate Homework Equations The Attempt at a Solution No idea what this question wants..? Is it something to do with the smoothness of...

hi all :) im trying to heat a metal wire in my experiment and because i don't have a heat sensor camera or an oven,... i thought of using a sand bath to control the heating temperature. is it possible to heat a wire upto 500~600 degree celcius by sand bath? (or whatever bath that may be...

Homework Statement A solid metal ball of radius 1.5 cm bearing a charge of -16 nC is located near a hollow plastic ball of radius 2 cm bearing a uniformly distributed charge of -4 nC on its outer surface. The distance between the centers of the balls is 8 cm. What is the electric field...

Homework Statement Consider two metal spheres of radii r1 = R and r2 = 2R, both charged to the same potential V0. a) What is the ratio n1/n2 of their surface charge densities?Homework Equations n(eta) = charge/area Er = -dV/drThe Attempt at a Solution a) n1/n2 = Q/(4*pi*R2) / Q/(16*pi*R2) = 4...

Homework Statement A long, straight wire is surrounded by a hollow metal cylinder whose axis coincides with that of the wire. The wire has a charge per unit length of lambda, and the cylinder has a net charge per unit length of 2lambda. From this information, use Gauss's law to find (a) the...

A uniform electric field of 1.0 N/C is set up by a uniform distribution of charge in the xy-plane. What is the electric field inside a metal ball placed 0.50 m above the xy-plane? E= Fe/q E=(kq1q2)/r^2 0= ((9x10^9)(1)(q2))/.5^2 q2= 0 does this sound right?

Right this is the question, Determine the yield stress for a metal with an average grain diameter of 0.045mm, if the yield stress for a metal changed from 650Nmm^-2 to 720Nmm^-2 when the average grain diameter decreases from 0.054mm to 0.037mm. I cannot figure this out, I've been trying...

Homework Statement A piece of metal of weight 50 grams is heated to a temperature of 100°C and then introduced into a calorimeter containing water at 14°C, the maximum temperature reached being 20°C. If the weight of the calorimeter is 5 grams, the specific heat of the metal of which it is...

Metal ions in Pyrex--why? According to http://en.wikipedia.org/wiki/Pyrex#Composition" is composed of oxygen, silicon, calcium, and sodium. I've Google Scholared to no avail... Thanks!

So I've just been thinking about how one could possible use Magnets/Electromagnets to repel from a metal. I came up with the following thought: Metal is attracted to a magnet because the magnet aligns the electrons in the metal to the opposite of the magnet (ie. a N pole put to a metal...

if you plunge a hot metal (like wire) into water, the water temperature obviously increases. I wonder what kind of heat transfer occurs between the metal and the water. it clearly doesn't seem like convection or radiation. But I am not so sure if conduction is the right one cos it is usually...

Homework Statement A metal ball is attached to a rope with length 2.40 m and swung in constant velocity in a circle with velocity 3.0 m/s A light at the same height casts a shadow from the center to 0.8 m, what is the velocity at this point?Homework Equations The Attempt at a Solution

Hi guys, I'm a physicist and would appreciate some direction in helping me understand the dynamics (or chemistry) of graphite in a bath of liquid metal. Eventually the bath is cooled into a solid ingot. There are several different metals which are used (Cu, Fe, Al as well as many alloys). Any...

9. Two sliding metal bars of length l = 15.0 cm are moving along two parallel rails, in opposite directions, with constant speeds of v = 0.7 m/s, as shown in the figure below. The rails are located in a uniform magnetic field with a magnitude 0.35 T that is directed into the page as shown...

I'm very confused about how metal hydrides form. I'm looking at PCI plots and I see what's happening, but I have no idea why it is. For instance: "Molecular hydrogen is dissociated at the surface before absorption; two H atoms recombine to H2 in the desorption process." Why does this...

I recently did an experiment in class that involved two parts, 1) the collision of 2 metal pucks 2) the collision of 2 magnetic pucks following the analysis, i discovered that in part 1, 75% of the original kinetic energy, and 93% of the original momentum was conserved after the collision...

A uniform flat plate of metal with dimensions 10x 12 is situated in a reference plane with its bottom left hand corner at (-2, -6) and its upper right hand corner at (8, 6). The plate has a circular hole cut out of it centered about (4,0) with a radius of 2. Find the x coordinate of the center...

Anyone know anything about induction cookers? Induction cooking? What if the lady sticks a metal spoon to stir the pan and is bare-foot? What prevents the eddy current from breaking out of the loop given the new path your body provides?

Homework Statement A mass of 225 kg is hung from a metal cable of length 1.60m and diameter 8.20mm. This causes the cable to stretch by an amount 0.668mm. Calculate the Elastic Modulus of the metal. Homework Equations E=(F/A)/(change L / orig L) The Attempt at a Solution F =...

The acid: Hydrochloric What happens step by step? I am unfamiliar with acids and bases, so I just want to know what's happening to help figure out. Thanks.

Homework Statement here's how the question goes: the magnitudes of the charges on two identical small metal spheres are in the ratio 5:1. the coulomb interaction force between them is F1. if they are brought into contact and then separated to their respective original positions, the coulomb...

Hey there, I have problems trying to understand how a metal detector works. I don't understand why the inductance of a coil changes when a metal is approaching. Can someone explain that to me ? :redface: Thanks a lot for your help

How do you calculate heat flux through a piece of metal?? Hello, I need to calculate heat flux in W/m2 through a small cylindrical steel bar measuring 12mm length x 2mm diameter. At one end of the bar the temperature is 31C (the heated side) and at the other end it's 28C. How do I calculate...

Homework Statement Imagine water in a metal bowl that is open to air. This metal bowl is grounded. You add some NaCl to the water. What would the distributions of the ions look like in the water. Homework Equations I think this doesn't need equations, but just general understanding...

Homework Statement Three rods of identical cross-sectional area are made from the same metal, form the sides of an isosceles triangle ABC right angled at B. The points A and B are maintained at temperature T and √2 T respectively in steady state. Assume that only heat conduction takes place...

Homework Statement Three cubes of equal lengths, lead, iron, and copper are arranged between heat boxes at 100C and 0C. The heat current between boxes is 155W. 1) What is the side length of the cube? 2) What is the temperature between the lead and iron cubes? Some k values are also...

If I had a strong magnet and was standing in metal shoes that were welded to a metal trashcan lid, could I levitate myself with said magnet?

i cannot understand why persistent current in a normal metal ring threaded by a magnetic field is a surprise. the hamiltonian is H=\frac{1}{2I}\left(-i \frac{\partial}{\partial \theta}-A\right)^2 and the eigenstates are \phi_m(\theta)=\frac{1}{\sqrt{2\pi}} e^{i m \theta} with...

I have a problem that requires me to do a simple simulation of a sheet metal stamping. I have access to Ansys Workbench v12 Academic version, and have familiarized myself with the program and tried to read up on its features and limitations. The simulation is selected as a static structural...

I'm having an issue solving a back titration problem. We need to identify the metal in a metal carbonate. It can either be a group 1A or 2A 1.8500 grams of the carbonate are diluted to .2500L and then 0.02000L is taken and mixed with 0.01500L of 0.1789M HCl in a flask. After shaking the...

Homework Statement I am trying to calculate the electric field between these two plates... and I am using two different methods to do so. One gives me the correct solution, and the other does not. I am curious as to why the second method is wrong. Homework Equations Gauss's Law Phi =...

Homework Statement A 90 kg metal slab is pulled across the ground by a tractor. The coefficient of friction between the slab and the ground is µ = 0.65. If the force of the tractor on the slab is 600 N and is directed at 35° from the horizontal, what is the acceleration of the slab...

if I have 2 spheres A and B initially neutral, isolated from ground and in contact with each other, when I bring a negatively charged rod near to sphere A, I understand that positive charges will be induced on A and negative charges on B. Suppose I were to ground the sphere (a wire either...