Recent content by AlchemistK

  1. A

    Energy in destructive interference.

    Homework Statement What happens to the kinetic energy of the system when two pulses interfere destructively? Exact Question: Two pulses in a stretched string whose center are initially 8 cm apart are moving towards each other as shown in the figure(Attached). The speed of each pulse is 2...
  2. A

    Mechanical force on unit area of charged conductor.

    OK, my confusion about S1 is from the fact that I thought that dS is actually not a real element but a hypothetical one, from when the complete smooth conductor was cut and gave rise to the surface of dS .Now that I think about it, its a terribly stupid mistake, since σ would change too if it...
  3. A

    Mechanical force on unit area of charged conductor.

    Homework Statement OK first, I didn't know where to post this since it is and is not homework,anyways, posting here would be safest. Now, the attached scan is a proof from my (not so trustworthy) textbook and I have some doubts in it. The first doubt is in statement S1 : Every element...
  4. A

    Does the Electric Field Rearrange Charges When Accelerating a Particle?

    By the statement that the particle comes in perpendicular to the fields, I only meant the initial condition, not that it was constrained throughout its motion.
  5. A

    Does the Electric Field Rearrange Charges When Accelerating a Particle?

    Or could it happen that the plates move towards each other and reduce the volume of the space containing electric field, ultimately reducing electrostatic energy?
  6. A

    Does the Electric Field Rearrange Charges When Accelerating a Particle?

    Just wandered in with a constant velocity perpendicular to the field lines. (somehow dodging fringing?) It wouldn't have potential energy if the thing that put it there didn't have to do any work, right?
  7. A

    Does the Electric Field Rearrange Charges When Accelerating a Particle?

    No, no! Let me start over. Electric field has energy, particle comes through, and electric field does work on it, particle gains kinetic energy. Electric field lost energy, but then, something must happen to change something about the electric field, if the magnitude of the electric field...
  8. A

    Does the Electric Field Rearrange Charges When Accelerating a Particle?

    That is what I'm concerned about, the energy lost by the field as qEdx, what happens to compensate that? Please neglect all imperfections including fringing.(Unless that is what's really causing it)
  9. A

    Does the Electric Field Rearrange Charges When Accelerating a Particle?

    What if we compare two instances when the particle is well inside the capacitor? There will be gain in vertical velocity (Keeping your diagram as reference) due to the acceleration it faces by the electric field. Philip Wood's diagram accurately represents my problem (minus the fringe effect...
  10. A

    Does the Electric Field Rearrange Charges When Accelerating a Particle?

    Suppose there are two parallel plates with charges of opposite polarity on the faces towards each other (a charged capacitor, disconnected) and we send a charged particle through the field between them from one end. When the particle comes out the other end, it has more kinetic energy, because...
  11. A

    What happens to cohesive forces when things break?

    Cohesive forces holds stuff together, these forces being strongest in solids. However, why don't things (say, a stone) stick back together if I push them close?
  12. A

    Thermodynamics : Heat transfer question.

    Homework Statement A solid body X of heat capacity C is kept in an atmosphere whose temperature is 300K. At t=0 temperature of X is 400K. It cools according to Newton's Law of cooling. At time t1 its temperature is found to be 350 K . At this time,the body X is connected to a large box Y...
  13. A

    Is the Universe Expanding or Has it Already Expanded?

    The expansion is increasing, and that too at an exponential rate. In fact, even faster than the speed of light.
  14. A

    Local Conservation of Charge: Feynman's Thought Experiment Explained

    I was watching the messenger lectures by Feynman and in the third lecture he talks about conservation. In the beginning he talks about the conservation of charge, and at one point demonstrates a thought experiment in which two observers, one stationary and the other moving, see a charge...
  15. A

    Can an angle be considered to be a vector?

    When we were taught about angular velocity , we were told that angle is not a vector since it does not follow the rules of vector operations. However, a very small angle CAN be considered as an angle.
Back
Top