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A metal is an element, compound or alloy that is a good conductor of both electricity and heat. They are generally shiny, malleable and ductile. Some elements and compounds are not classified as metals unless under high pressures when they begin to act as metals.

Metallic substances atoms are closely positioned to neighboring atoms in either two possible arrangements. The first arrangement is body-centered cubic. In this arrangement, each atom is positioned at the center of eight other atoms. The second arrangement is face-centered cubic. In this arrangement, each atom is positioned in the center of six others. These two different arrangements form crystal structures. Structures of metals can change depending on the temperature.

Atoms from metallic substances can lost their outer shell electrons. This results in a free flowing cloud of electrons within their otherwise solid arrangement. It provides the ability of metallic substances to easily transmit heat and electricity. The solid characteristic of metals during this flow of electrons occurring is produced by electrostatic interactions between each atom and the electron cloud. This is called metallic bonding.

Metals are inclined to form cations through electron loss reacting with oxygen in the air to form oxides over various timescales. Transition metals (iron, copper, zinc) are slower to oxidize because they form passivation layers of oxide that protects the interior. Other metals such as palladium, platinum and gold, do not react with the atmosphere at all. This is due to the barrier layer of oxide which is formed on the surface which is impenetrable by further oxygen molecules. This allows those metals to retain their shiny appearance and good conductivity.

Alloys are a mixture of two or more elements, which the main component is a metal. Often pure metals are either to soft, brittle or chemically reactive for practical use. Combining different ratios of metals makes alloys have the desirable properties of the pure metals. Common alloys will incorporate aluminium, titanium, copper and magnesium.

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Electromagnetic Induction: Metal Ring Surrounded By Magnet

A metal ring 4.80 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 field to remain uniform but decrease steadily at 0.210 T

What speed to produce a current?

A metal rod is sliding to the right on two metal rails separated by a distance L = 0.25 m. The rails and the rod have zero resistance, but the rails are connected by a 12.6  resistor, and the entire system is in a uniform magnetic field of magnitude 0.93 T. What is the speed at which the metal rod must be moved in order to pr

Density: To find Density of solid using graduated cylinder.

Problem: A piece of solid metal weighing 322 grams is placed into a graduated cylinder, which is then filled with liquid mercury. The metal does not float. After weighing the cylinder and its contents the solid metal is removed and the cylinder is then filled with more liquid mercury to the same level as before. Now the cyli

Skin Depth in Conductors

a. Show that the skin depth in a poor conductor (sigma << WE) is (2/sigma) (E/mu)^1/2 when independent of frequency. Find the skin depth (in meters) for (pure) water. b. Show that the skin depth in a good conductor (sigma >> WE) is lambda/2pi (where lambda is the wavelength in the conductor). Find the skin depth (in nanometer

Rate of heat conduction

A metal bar is used to conduct heat. When the temperature at one end is 100.0 degrees C and at the other is 20.0 degrees C, heat is transferred at a rate of 16 J/s. If the temperature of the hotter end is reduced to 80.0 degrees C, what will be the rate of heat transfer?

Scattering Mechanism in Metals

Consider the thermal conductivity K of a pure synthetic sapphire crystal that has a diameter of 3mm. (For sapphire delta D -1000 K , speed of sound - 10^4ms^-1, and for T <<delta D, cv - 10^-1 T^8 J M K^-1, delta D is the Debye temperature and T is the temperature). a. Discuss which scattering mechanism dominates the thermal

Metal Linear Expansion Problems

1. At room temperature (23C), a metal ball just fits through a metal ring. 2. If the ball is heated up 50 degrees (change in temperature is 50 degrees), the ball won't fit. Explain why the ball won't fit. 3. If we heat up the ring only, does the ball fit? Why or why not?

Linear expansion of metals and other physics problems

The coefficient of linear expansion of aluminum is 0.000023/C. A circular hole in an aluminum plate is 2.725 cm in diameter at 0C. What is the diameter of the hole if the temperature of the plate is raised to 100C? A child wants to pump up a bicycle tire so that its pressure is 250 X 10 Pa above that of atmospheric pressure.

Electrical Charge Carried by an Isolated Metal Sphere

An isolated metal sphere of radius R( one) carries an electrical charge Q. A second sphere of radius R (second) and initially uncharged is brought into contact with the first sphere. Charge is exchanged between the two and they are separated. How much charge remains on the first sphere?

Magnetic flux threading a metal ring varies with time

The magnetic flux threading a metal ring varies with time t according to 3at^3-bt^2, with a = 7.7s^-3m^2T, and b = 2.8 s^-2m^2T. The resistance of the ring is 2.3 Ohms. Determine the maximum current induced in the ring during the interval from t1 = -2.3 s to t2 = 7.3 s. Answer in units of A

Temperatures of two similar metal spheres differently fixes

Temperatures of two similar metal spheres differently fixes in the space. The problem which does not need calculations but only a correct understanding of the applied energy distribution. Two similar metal spheres are located at the same height from the earth surface. The first is pended on the end of a rod and the second is

Charges and Neutral Metal Spheres

Imagine that you have two identical neutral metal spheres on insulating stands and a charged rubber rod. Using diagrams, carefully describe a step-by-step process that uses the rod to give the two spheres exactly opposite charges (all without touching either sphere with the rod). Take care to construct your procedure so that it

center of mass of sheet metal with a curved edge.

See attached file. A thin, uniform piece of sheet metal in an x,y plane has one side along the x axis from (0, 0) to (3, 0), and a vertical side from (3,0) to (3, 5.4). The remaining side is curved between (0,0) and (3, 5.4) on the line y= .6 x^2. Find xcm, the x coordinate of the c.m. SEE ATTACHMENT #1 for a diagram of