what is Contact potential?
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The voltage generated by the contact of two dissimilar metals or materials, or the same metal at different temperatures. (from ref.) Sounds a bit like thermoelectric potential (what makes a thermocouple work) but not the same...
663820
It may be surface tension.
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Place a drop of water on horizontal glass plate gently.\n\nContrary to our expectation that the contact area should be a perfect circle, the area will have an irregular area.\n\nIf we clean the glass thoroughly and repeat the experiment we can see that the area is some what circular.\n\nThis shows that only if the glass plate is perfectly clean and has a perfectly plane, t surface (with out any surface waviness) the area of contact will be circular.\n\nThe surface tension between the glass and water makes the surface of water to be at an angle called angle of contact.\n\nIf the glass contains impurities and if the surface is not perfectly plane  then the angle of contact will not be uniform and constant and hence the area of contact is of some irregular area.\n\nIn a vertical window pane, the gravity pulls the water drop and and at each point of contact, the surface tension prevents the pull at different angle due to the variation of surface tension at each point due to impurities and surface waviness.\n\nThe water moves along the resultant force which is not uniform. \n\nThis is the reason that the water is not moving straight down.\n\nIf the water goes almost straight down we can conclude that the glass is almost clean.
613346
The previous responses are right but ko is not a potential. It's the (average) momentum for a particle in free space. With psi defined by:\n\npsi(x) = A exp(ikx - x^2/(2sigma))\n==>\npsi*(x)psi(x) = |A|^2 exp(-x^2/sigma)\n\nYou need the integrals:\n\n&#92;int_(-oo)^(+oo) exp(-x^2/sigma) dx = sqrt(pi*sigma)\n&#92;int_(-oo)^(+oo) exp(-x^2/sigma) x^2 dx = (sqrt(pi)/2) sigma^(3/2)\n\n<x^2> is the second expression divided by the first:\n\n<x^2> = 1/(2 sigma)\n\nSince H = p^2/2m, \n\nH psi(x)\n= -(1/2m)(d^2/dx^2) psi(x)\n= -(1/2m) [(ik-x/sigma)^2 - 1/sigma] psi(x)\n= (1/2m) [k^2-x^2/sigma^2 + 2ikx/sigma + 1/sigma] psi(x)\n\n==>\n\n<H>\n=(1/2m)[k^2-<x^2>/sigma^2 + 2ik<x>/sigma + 1/sigma]\n=(1/2m)[(k^2+1/sigma-(1/2sigma)]\n=(1/2m)[(k^2+1/(2sigma)]
580059
If you take a ball and hold it out at arms length, it has potential energy. This energy is being held back by your hand and once you release the ball, gravity turns that potential energy into kinetic energy (movement) and makes it hit the floor.
1162367
'Electrostatic'= electricity at rest. This distinction has been made because the forces exerted by a moving charged particle and one at rest r different. The moving (accelerating) one has an associated magnetic field,  as well as energy due to its motion (electric current). But, in colloquial terms static electricity is a term used for the electric potential differential produced when 2 articles r rubbed (say glass and wool), which upon doing so develop opposite charges and r attracted. This force is directly proportional to the magnitude of charge and inversely to the sqaure of the distance between them (inverse-squared law; just like the gravity and magnetism). Bye. Take care.
42550
Potential, kinetic, chemical, electrical, and thermal.
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1. potential\n2. kinetic\n3. it left at 0\n4. friction\n5. the greater the mass, the less  distance\n\nYour source of errors and improvements must come from your lab
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Neither, what it does is increase the rate of a reaction since all reactions require direct contact between reactants, the more contact (higher surface area) the faster the reaction occurs.\n\nBut, overall, the energy remains the same.
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Live point is at high potential and neutral is at zero potential.\n\nThe Earth point is connected to earth which is also at zero potential.\n\n One of the terminals of any electrical appliances is connected to live and the other to neutral to complete the circuit.\n\nThese appliances usually have metal parts for covering and for some specific purposes. (Example- iron in iron box) \n\nWhen handling these appliances there is always a chance for the live wire to make contact with the metal parts of the appliances by accident. And they acquire high potential. This, if we touch the appliances unknowingly it may lead fatal consequences.\n\nOn the other hand if these metal parts are properly earthed, if by accident live wire touches the metal parts then at once it is earth connected and  due to heavy current the fuse blows off, preventing any probable accident.
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DUE TO SURFACE TENSION POSITIVE ANGLE OF CONTACT AND INTERNAL PRESSURE.
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One of my physics professors believed we can never truly touch anything.  The outer part of every atom is the electrons.  Since electrons are all negative, when we try to touch something our own electrons would cause a repulsion of the electrons in the object we are trying to touch.  He believed that we actually feel the electrons repelling each other - not the actual object.  The electric repulsion would be too great for our hands to actually touch the object.
1091953
Analyzing the interactions between and examining the existence of, particles.
735355
Look up "Madelung" in your textbook (if you have one) you will find that (ignoring repulsion) lattice energy is proportional to\nZ^2/r (Z is charge and r is distance).
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E potential = mgh\n= 4 kg ( 9.81 m/s^2) ( 2.5)\n=98.1\n\nPotential energy was not lost....it transformed into Kinetic Energy\n\nKinetic + Potential = Total Energy\n\nLaw of Conservation of Energy
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"A potential gradient (E) is the local space rate of change of the potential.\n\nIn electrostatics then, it is the local space rate of change of the electric potential:\n\n    E = - delta V / delta s\n\nUnits are volts per meter (V/m). The electric field is the same as the potential gradient but with opposite sign."\n\nFrom Wikipedia,\nhttp://en.wikipedia.org/wiki/Potential_gradient\n\nHope this helps!
464446
Gravitational potential = G *Mass of the earth/radius of the earth.\nIn other words its equal to Gravitational energy per unit mass.