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GCSE q:how does resistance in a circuit increase temperature, in terms of electrons? watch

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    Hi, I'm doing some research for GCSE physics coursework and I was wondering about how exactly resistance in a metal wire in a circuit increases its temperature in terms of electron movement. When the electrons in the current collide with atoms in the component/wire, is heat generated when
    a) the collision generates kinetic energy as the atoms vibrate which is then converted to heat energy, or
    b) the voltage used to 'push' the electrons along is dispersed in a collision as heat energy

    Thanks.
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    Hi, I'm doing some research for GCSE physics coursework and I was wondering about how exactly resistance in a metal wire in a circuit increases its temperature in terms of electron movement. When the electrons in the current collide with atoms in the component/wire, is heat generated when
    a) the collision generates kinetic energy as the atoms vibrate which is then converted to heat energy, or
    b) the voltage used to 'push' the electrons along is dispersed in a collision as heat energy
    The voltage provides the energy to move the electrons, which in turn hit the lattice and convert some of their kinetic energy (that they gained by being accellerated across a potential difference) into lattice vibrations (see phonons if you're interested for more details). It is these lattice vibrations that are observed macroscopically as heating of the wire.
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    (Original post by spread_logic_not_hate)
    The voltage provides the energy to move the electrons, which in turn hit the lattice and convert some of their kinetic energy (that they gained by being accellerated across a potential difference) into lattice vibrations (see phonons if you're interested for more details). It is these lattice vibrations that are observed macroscopically as heating of the wire.
    So, basically, as the electrons collide with atoms in the conductor, their kinetic energy is converted to heat energy in the wire?
    Thanks!
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    So, basically, as the electrons collide with atoms in the conductor, their kinetic energy is converted to heat energy in the wire?
    Thanks!
    Exactly.
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    (Original post by spread_logic_not_hate)
    Exactly.
    Does the collision generate kinetic energy itself though, like cause vibrations faster, or is it just the existing electrons' kinetic energy that generates the heat energy?
    Thanks!
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    Does the collision generate kinetic energy itself though, like cause vibrations faster, or is it just the existing electrons' kinetic energy that generates the heat energy?
    Thanks!
    The collision itself doesn't generate kinetic energy - it converts some kinetic energy of the electron into vibrational energy in the lattice, which is seen as heat.

    Think of it as the electron hits the lattice, slows down (because it loses kinetic energy) and makes the lattice vibrate because it hit it.

    Best analogy in real life - throwing paper through a spiders web. The paper slows down a little as it hits the web, and the web shakes around all over the place because the paper hit it!
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    (Original post by spread_logic_not_hate)
    The collision itself doesn't generate kinetic energy - it converts some kinetic energy of the electron into vibrational energy in the lattice, which is seen as heat.

    Think of it as the electron hits the lattice, slows down (because it loses kinetic energy) and makes the lattice vibrate because it hit it.

    Best analogy in real life - throwing paper through a spiders web. The paper slows down a little as it hits the web, and the web shakes around all over the place because the paper hit it!
    Ah I think I get it now- so no kinetic energy is generated by the collision, the moving electron has kinetic energy and as it collides with an atom of a wire, it makes the atom vibrate, and therefore some of the kinetic energy from the electron is converted to heat energy in the atoms of the wire.
    Is that right? I'm just wondering how to word it in my coursework, lol.
    Thanks!
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    Ah I think I get it now- so no kinetic energy is generated by the collision, the moving electron has kinetic energy and as it collides with an atom of a wire, it makes the atom vibrate, and therefore some of the kinetic energy from the electron is converted to heat energy in the atoms of the wire.
    That's it. Make sure either 'converted' or 'tranferred' is in the description and you'll be fine!
 
 
 
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