Metal Definition and 999 Threads

  1. E

    How to get spectra from a metal?

    Don't exactly know where to put this but how would one examine the spectra of a metal ore to find what is in it? That being, not using a mass spectrometre.
  2. K

    Heat transfer through two metal bars

    Homework Statement A steel bar 10cm long is welded end to end to a copper bar 20cm long. Both bars are insulated perfectly on their sides. Each bar has a square cross section, 2cm on a side. The free end of the steel bar is maintained at 100 celsius and the free end of the copper bar is...
  3. E

    Gauss's Law for cylindrical metal tube enclosing a wire (coaxial cable)

    Homework Statement Immediately outside a very long cylindrical wire of radius r1 = 1mm, the electric field is 40kV/m directed towards the wire's surface. A hollow cylindrical metal tube with inner radius r2 = 3mm is now placed around the wire, to form a coaxial cable. What will be the charge...
  4. J

    Would metal hitting metal or metal hitting glass make more noise?

    If you have a lump of metal would it make a louder noise if it hit glass or metal?
  5. M

    Metal bar on conducdting rod take 2 (didn't post first time)

    . Homework Statement A metal bar is free to slide without friction along two parallel metal rails. The circuit is completed by a battery. (conducting bars are in the x direction, left side of drawing the conducitn bars are connected by a battery, the right side is where the metal bar is) If...
  6. C

    [PhD Qualifier] Charged rod above metal plate

    Hey ... I'm trying to study for my PhD qualifying exam, and I have a bunch of questions from previous years, but no answer keys. Homework Statement A think uniformly charged rod of length L is positioned vertically above a large uncharged horizontal thick metal plate. The distance between...
  7. T

    Separating Metal Alloys - Learn How to Do it

    This question came up at work. Can metal alloys be separated into their constituent components? How? Thanks.
  8. C

    Why am I getting electrocuted by metal after my hand implant was removed?

    hi, I'm a web developer so i usually stay in front of a computer for almost 12 hrs a day. my question is, when i get up from my computer and hold a metal, ex. faucet or a spoon, or even a refrigerator holder i get electrocuted. FYI, by the way, i got a surgical implant in my right hand...
  9. Q

    Does Gasoline Cause Metal to Rust Compared to Water?

    If yes how about in comparison to water? I ask cause I was wondering how they stop the metallic fuel injection tubes from rusting out. Is there a coating or does it just not rust in presence of gasoline? Im assuming that gasoline doesn't rust since its a hydrocarbon and water contains O, and...
  10. G

    What causes charge to only reside on the surface of a hollow metal sphere?

    Why does charge given to a hollow metal sphere reside only on its surface?
  11. G

    Residual stress induced by metal deposition on cantilever

    hi, everyone, now I am trying to deposite some metal layers on micro-scale cantilever surface on the purpose of bending it under the residual stress caused by metal deposition. I read some literatures which mentioned and even gave the exact value of residual stress happened in both the...
  12. A

    Solving the Problem: Lever & Metal Wedge in Water

    hi.. i have a problem that i need to solve.. in the attached mage, there is a submerged object in water cousing na upward lift force of 100kg. above it is a lever with a weigh attached to it weighing at 90kg. wll this weight difference be enough to move the metal wedge from point a into point...
  13. C

    Calculating Electric Field of a Metal Sphere

    A metal sphere of radius R = 10 cm carries a total charge Q = 0.4 μC. A. What is the magnitude of the electric field just outside the sphere, and in which direction is it pointing? B. What is the magnitude and direction of the electric field just inside the sphere? I have already found...
  14. R

    Help with Water, Ice, and metal finding temperature

    Homework Statement A 50-g of ice, initially at 0.0C, is dropped into 200 g of water in an 80-g aluminum container, both initially at 30C. What is the final equilibrium temperature? (Specific heat for aluminum is 900 J/Kg*C, the specific heat of water is 4186 J/Kg*C, and...
  15. C

    Will a Metal Sphere's Charge be Uniformly Distributed?

    Just wondering: If a metal sphere is charged, will the extra charge be uniformly distributed over the volume of the sphere. i think that it will? but not sure about it being uniformly distributed.
  16. G

    What is the speed of sound in the metal?

    Homework Statement A metal tube with length 931m is hit with a hammer. On the other end two sounds with time delay of 2.5 seconds can be heard. What is the reason for this? What is the speed of sound in the metal? Homework Equations t=L/v The Attempt at a Solution I think the...
  17. F

    Be2Si: Group Symmetry Requirements of a Metal

    Dear friends, I'm having trouble understanding an article by M. Cohen and J. Corkill (Structural, bonding, and electronic properties of IIA-IV antifluorite compounds). In this article Be2Si (an imaginary compound) is shown to be a metal. The argument used is GROUP SYMMETRY :... group symmetry...
  18. H

    Is the Fields Medal Age Limit Justified?

    Why is it that one must be under 40 to be eligible for a Fields Metal? Are they implying old farts can't do math? I wonder what Archimedes would say about this...
  19. P

    Witnessing Electric Arc Furnace Melting Metal with Programming

    good day, this place is great, and i just got questions an AC electric arc furnace melts metal by way three electrodes and electric arcs generated by potential differences inside the furnace i had the opportunity to watch one in action and understanding the programming i see it controls...
  20. A

    Induced Electric Fields of metal ring

    Homework Statement A metal ring 4.50 cm in diameter is placed between the north and south poles of large magnets with the plane of its area perpendicular to the magnetic field. These magnets produce an initial uniform field of 1.12 T between them but are gradually pulled apart, causing this...
  21. B

    Questions on electrons incident on a metal surface

    Homework Statement Electrons with kinetic energy E are incident normally from vacuum on a metal surface. The work function of the metal is F. Calculate the fraction of electrons reflected from the surface. Neglect any temperature effects. Homework Equations The Attempt at a...
  22. J

    Is Titanium the Solution for Rust-Proof Solar Panel Mesh?

    I'm having trouble finding a suitable material to keep critters from nesting under our solar panels. Galvanized steel mesh oxidizes quickly because being attached to the solar modules, and plastic mesh just isn't strong enough and looks unsightly. I need a steel or metal mesh that will not...
  23. C

    What are your favorite metal bands?

    Metal Bands! Which ones are youre favorites? I envy those of you who lived through the 80's listening to stuff like AC DC, Maiden, Led Zep, GnR. Music was HUGE then! I mean, the money's still there, but rockstars were Gods man! I don't think there's anyone in music today who's as big or iconic...
  24. wolram

    Treasure hunting metal detectors

    How do they discriminate between good (targets ) and rubbish, it seems that the orientation of the (Target) can fool the detector, from using one of these detector for many years , i find that the depth of the (Target) is instrumental in the discrimination, and only after years of (detecting)...
  25. K

    How Does Gauss' Law Apply to the Electric Field Around a Charged Metal Ball?

    Homework Statement A metal ball with radius R = 0,6 m is charged with Q = 0.15 nC. Find the electrical field as function of the distance r from the center of the ball. The Attempt at a Solution Gauss law: Q = e0*E(r)*A = e0*E(r)*4*pi*R^2 which gives E(r) = Q /...
  26. D

    How Does Grounding Affect Charge Distribution in a Metal Sphere?

    I'm trying to get a better understanding of this sort of thing. Here is what I know... A postive point charge "q" is placed at the center of an uncharged metal sphere insulated from the ground. The outside of the sphere is then grounded from the outside. Then the ground wire is removed. A is...
  27. E

    Capacitance and Inductance of Thin Metal Ribbons

    Homework Statement 21. A certain transmission line is constructed from two thin metal “ribbons”, of width w, a very small distance w<<h apart. The current travels down one strip and back the other strip. In each case it spreads out uniformly over the surface of the ribbon. a) Find the...
  28. P

    Potential of a metal sphere with changing radius

    Homework Statement An inflatable metal balloon assumed to be spherical with radius R is charged to a potential of 1000 V. After all the wires and batteries are disconnected, the balloon is inflated to a new radius 2R. Does the potential of the balloon change as it is inflated? If so, by what...
  29. T

    Can Hitting Metal Make it Magnetic?

    If you take a screwdriver for example, and hit it a few times near the tip with a hammer or something hard; why does the screwdriver become magnetic? I was shown someone doing this, and shortly afterwards it was able to attract nails or screws around.
  30. L

    Metal in Microwaves: Glass or Metal?

    A compact disc contains an extremely thin sheet of aluminum. If you put a larger block of metal in a microwave oven along with a CD and turn the oven on, a) nothing significant happens b) only the metal will spark and then melt c) the metal will melt and the CD will spark d) only the CD...
  31. C

    A Proton is orbiting a metal ball

    Homework Statement A proton orbits a 1.0-cm-diameter metal ball 1.90 mm above the surface. The orbital period is 1.50 \mu s. What is the charge on the ball? Homework Equations F_{cp} = \frac{m v^2}{r} F_c = \frac{k q_1 q_2}{r^2} The Attempt at a Solution Since the proton is...
  32. A

    Math Metal: Meshuggah Beats & Timing Explained

    Anyone heard of the band Meshuggah? Their beats and timing are very interesting. Like windshield wipers on different cars, oscillating at slightly different frequencies. I Just thought they must be into math and physics.
  33. N

    Calculating Angular Acceleration of a Metal Plate

    Homework Statement A metal plate in the shape shown has a mass of 2.00kg and hangs from a pivot point located a distance d=0.300m from its center of mass. Its moment of inertia, I_cm, about an axis perpendicular to the plate and passing through the CM is 0.210kg*m2. Calculate the magnitude...
  34. I

    The capacitance of the two metal sphere system

    the capacitance of two metal sphere system Homework Statement What is the capacitance of the two metal sphere system. *The question has been attached shematically. All the variables are given in the attached file, there is no missing variable. thx for any help.
  35. F

    Metal Wire in Equilibrium & Steady-State

    Hi all, I've been struggling with the concept of equilibrium and steady state in a metal wire. Can anyone of you please help me get this important concept down? I'd really appreciate it. -- Homework Statement Which of the following statements about a metal wire in equilibrium are...
  36. A

    What Causes Metals to Conduct Heat?

    Hi, I understand what make metal a conductor of electricity, but what allows it to conduct heat? Is it that it does not absorb heat because it's electrons are easily liberated?
  37. Y

    Metal in Microwave: Heating Up Water and Spoons?

    When you put a metal (conducting) spoon inside a microwave, it takes a few seconds, and then you get sparks, that might damage the microwave. I heard (and cowardly hadn't tested) that putting a spoon inside a cup of water would allow a long 5 minute heating, no sparks and no damage. The riddle...
  38. K

    Solving a Copper Metal Heat Exchange Problem: Seeking Advice

    Just looking through some old papers and found a problem that I don't know how to solve. Two identical 1.0-kilogram blocks of copper metal, one initially at a temp OC and the other initially at a temp of 100C are enclosed in a perfectly insulating container. The two blocks are initially...
  39. U

    End of electrons leaving metal

    Zapper, you're so full of assumptions that it's impossible to communicate with you. Did I say it's relevant? It's an apology I think you owe me. I know it was NOT malicious, it probably just didn't compute so you ignored it, until you were reminded of high voltage coils. But apologies should...
  40. D

    Maintenance-Free Shine: Choosing the Right Metal for Auto Emblems

    Which metallic material will have a maintenance free shine when polished? I want to machine auto emblems so I'm looking for a material that does not go dull when expose to the elements. Thanks!
  41. U

    Why don't electrons leave a negatively charged metal in air?

    I'm familiar with lightning rods taking advantage of the mutual repulsion of charges to shoot off a corona discharge off the sharp end and start a thunder, but why doesn't corona discharge happen to all charged metals? What makes air such a good insulator, when it's just gases, relatively few...
  42. P

    How Does Heat Transfer Through Welded Metal Bars Differ?

    Homework Statement A steel bar 10cm long is welded end-to-end to a copper bar 20cm long. Both bars are insulated perfectly along their sides. Each bar has a radius of 2.0cm. The free end of the steel bar is maintained at 100 degrees C and the free end of the copper bar is maintained at 0...
  43. S

    Negative rod to uncharged metal ball:

    [SOLVED] negative rod to uncharged metal ball: Homework Statement If a negatively charged rod is held near an uncharged metal ball, the metal ball: 1. becomes positively charged. 2. becomes polar. 3. Effect cannot be determined. 4. becomes negatively charged. 5. is unaffected. The...
  44. J

    Calculating E-Field Close to a Metal Plate from an Infinite Charged Rod

    Homework Statement An infinite, thin, uniformly charged rod (charge density lamda) is situated parallel to a metal plate at a distance d above it. Calculate the E-field close to the surface of the plane as a function of perpendicular distance to the rod. The Attempt at a Solution I...
  45. G

    How Do You Calculate the Electric Field Inside and Outside a Charged Metal Tube?

    hey guys i was wondering if anyone could help me with this question, kinda got stuck Homework Statement Figure 24-31 shows a section of a long, thin-walled metal tube of radius R = 5.56 cm, with a charge per unit length λ = 7.34 x 10-8 C/m. What is the magnitude E of the electric field at...
  46. G

    Thermal Expansion of Metal Ball Problem

    [SOLVED] Thermal Expansion Problem Homework Statement A metal ball is just able to pass through a metal ring. When the ball is heated thermal expansion will not allow it to pass through the ring. What would happen if the ring rather than the ball, were heated? Would the ball pass through...
  47. S

    Property of the metal defines the ring's resistance to "opening"

    hello! i am quite new to material engineering and so my question might seem a bit too obvious. her it is: i have a metal ring-(picture1(304 stainless steel)) i need to know what property of the metal defines the ring's resistance to "opening"- like shown in the second picture thank you very...
  48. E

    Metal Matrix Composites (where to buy?)

    Hello! I am a grad student and am trying to acquire some Aluminum Metal Matrix composites with Boron Carbide reinforcement (15-20%) for research. I need the material to be in 1/4" thick sheets. Does anyone know of any companies that sell this sort of material? Thanks!
  49. A

    Calculating Temperature & Heat Transfer with a Piece of Metal

    A piece of metal with a mass of 1.50 kilograms, specific heat of 200 J/kg · C°, and initial temperature of 100° C is dropped into an insulated jar that contains liquid with a mass of 3.00 kilograms, specific heat of l,000 J/kg · C°, and initial temperature of 0° C. The piece of metal is removed...
  50. T

    Rectangular Membrane Metal Gauge Design: Research by Thangamani

    Dear Sir, This is Thangamani, doing research on sensor design. I have gone through Mr. Robert Dean (RF CMOS Designer, MEMS Optical, Inc) article that available on internet ( if not mistaken its from MEMS forum) discussed analytical solution about rectangular membrane. Since i am...
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