What is Point: Definition and 1000 Discussions

The melting point (or, rarely, liquefaction point) of a substance is the temperature at which it changes state from solid to liquid. At the melting point the solid and liquid phase exist in equilibrium. The melting point of a substance depends on pressure and is usually specified at a standard pressure such as 1 atmosphere or 100 kPa.
When considered as the temperature of the reverse change from liquid to solid, it is referred to as the freezing point or crystallization point. Because of the ability of substances to supercool, the freezing point can easily appear to be below its actual value. When the "characteristic freezing point" of a substance is determined, in fact the actual methodology is almost always "the principle of observing the disappearance rather than the formation of ice, that is, the melting point."

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  1. V

    Comp Sci Converting Float to Char in C: Exploring the Use of sprintf

    I am very new to C programming so am struggling with this question and how exactly to begin it, when we are doing this are we to use something like sprintf? Thank you.
  2. J

    Prove: Limit Point of H ∪ K if p is Limit Point of H or K

    Summary: Definition: If M is a set and p is a point, then p is a limit point of M if every open interval containing p contains a point of M different from p. Prove: that if H and K are sets and p is a limit point of H ∪ K,then p is a limit point of H or p is a limit point of K In this proof I...
  3. jackkk_gatz

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    I have tried to use the intial velocity v=(2gH)^(1/2) and tried to use conservation of energy, using potential energy to find the maximum height but still can't arrive to the answer provided. Don't know what concepts are relevant here, apparently I can't use velocity neither cosine or sine. I...
  4. G

    I At which point is gravity inconsistent with quantum mechanics?

    I'd like to understand how gravity does not combine with quantum mechanics. At least there is no accepted theory of quantum gravity, so I assume it is not solved? I'm only starting to learn QFT and eventually GR. Maybe, someone can already outline where those theories fail to combine and comment...
  5. TheHeraclitus

    I Carlo Rovelli, loop quantum gravity and point particles

    I am reading a popular-science book Reality Is Not What It Seems by Carlo Rovelli, one of the founders of loop quantum gravity. He writes: and and So basically, space (spacetime) is just another quantum field like all the others, and the quanta of this field is the nod. Nods have volume...
  6. A

    What is the current scientific consensus on myofascial trigger points?

    What is your thought and experience about it? What the mainstream consensus about it by general populations and by experts?
  7. Ahmed1029

    Laplace's equation when there is a point dipole

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  8. D

    B Question about collisions -- Knife point piercing a ball of clay

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  9. S

    How to determine the car's deceleration at a point along a curve?

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  10. M

    B Does a body behave as a point mass even at rest?

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  11. Tesla In Person

    Electric field strength at a point due to 3 charges

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  12. Ahmed1029

    Griffith's problem 4.37 -- A point dipole at the center of a sphere of linear dielectric material

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  13. M

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  14. Pipsqueakalchemist

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  15. G

    I How Can Outward Normal Vector Point Inwards?

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  16. chemisthypnos

    Searching for Low Impact Fluid with Boiling Point of 150-180 F

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  17. R

    Centre of Mass/Tipping Point Question

    I drew out a small diagram to illustrate my attempt. I interpreted 280 degrees from the vertical as 10 degrees from the horizontal. Using trig I solved for the h, which I get an obviously incorrect answer. The actual answer in the book is 2.3m,
  18. S

    I How to make the deflection equation at any point along a snow ski profile?

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  19. K

    I Retarded potential of a moving point charge

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  20. link223

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  21. newbie1127

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  22. P

    I Polygon Coordinates given the Area and Center point

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  23. D

    Engineering Solve BJT Transistor Q Point Using Thevenin Theorem

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  24. egoodchild

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  25. U

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  26. LCSphysicist

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  27. R

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  28. B

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  29. A

    B Locus of a Point: Get Help Now

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  30. J

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  31. chwala

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  32. G

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  33. S

    Question about elastic limit and yield point

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  34. guyvsdcsniper

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  35. J

    Find the electric field at a point away from two charged rods

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  36. drooble122

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  37. guyvsdcsniper

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  38. guyvsdcsniper

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  39. emmanual

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  40. A

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  41. S

    Gravitational Field and Potential at certain point

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  42. R

    I Can we predict the path of the Sun from a single observation point along the transit?

    Hi. I have this idea that might be useful for celestial navigation. If you were on a random place on the Earth, and you had a way of measuring the altitude of the sun above the horizon, at a precise moment, could you then predict the complete path, such that you could determine the altitude at...
  43. jackal123

    Finding Lagrange Point L2: Gravity and Harmonics

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  44. S

    Finding potential at a point in capacitor

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  45. S

    B Surface that when superimposed takes any one point to any other point

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  46. L

    Magnetic Surface Currents and the Interaction of Magnetic Fields with Matter

    From the graph we see that at ##H=4 kA/m,\ B=1.5T##. We have that ##M=\frac{B}{\mu_0}-H=\frac{1.5T}{\mu_0}-4kA/m## and from Ampere's Law that ##i=\frac{HL}{N}=\frac{4kA/m\cdot 0.1 m}{100}## and the current (density on the surface is) ##\sigma_{m}=M##. Does this make sense? I am having...
  47. H

    Angular momentum of the particle about point P as a function of time

    I don't understand why my solution is wrong. Here is my solution. $$ r_{\theta} = R\cos{\theta} \vec{i} + R\sin{\theta} \vec{j} $$ $$ v_{\theta} = v\cos(\theta + \frac{\pi}{2}) \vec{i} + v\sin(\theta + \frac{\pi}{2}) \vec{j} $$ $$ p_{\theta} = mvR(-\sin{\theta}) \vec{i} +mvR(\cos{\theta}...
  48. D

    I Geometric Point of View of sets

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  49. S

    I Is this statement an aspect of the Hairy Ball or Fixed Point Theorem?

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  50. greg_rack

    I Exploring Acceleration at Contact Point Between Wheel and Surface

    Hello guys, I am getting more and more confused each time I try to get a definitive answer on this doubt: what's the acceleration at the contact point between a surface and a wheel spinning on it(without slipping). Considering this standard FBD for the above-described situation, (the direction...
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