CrazyEngineers
CrazyEngineers

  • electron movement in AC

    somuumos

    Member

    Updated: Oct 26, 2024
    Views: 1.2K
    In a DC supply the movement of electron is from negative terminal to positive but how does a moving electron produce alternating current. does the same electron move back and forth...
    0
    Replies
Howdy guest!
Dear guest, you must be logged-in to participate on CrazyEngineers. We would love to have you as a member of our community. Consider creating an account or login.
Replies

  • Ramani Aswath

    Member • May 1, 2014



    Read the section on direct and alternating current here:
    #-Link-Snipped-#
    Are you sure? This action cannot be undone.
    Cancel

  • somuumos

    Member • May 2, 2014

    sir i got the concept partially but my ultimate doubt is that weather the electron deposits in the positive side as if in the direct current source such as battery of the ac source. And does the same electron electrons flows back and forth through a bulb if connected across a ac source.
    Are you sure? This action cannot be undone.
    Cancel

  • Ramani Aswath

    Member • May 2, 2014

    There is no separate identity for an electron. They are all identical. In a conductor there are free electrons and bound ones. The bound ones remain attached to a particular nucleus and do not move. The free electrons also called conduction electrons keep wandering around randomly when there is no EMF across the conductor. The moment a voltage appears electrons move from wherever they are towards the positive electrode.
    In a DC circuit they end up at the positive electrode of the ultimate power source.
    In an AC circuit they oscillate about a mean position. If the total circuit length is small the distance moved may be enough to let a particular electron to enter the source and be swallowed even in an AC circuit. However, another electron will have to move back in the next half cycle.

    I am afraid that the statement that the same electron moves back and forth does not hold water.
    Are you sure? This action cannot be undone.
    Cancel

  • somuumos

    Member • May 2, 2014

    oh yes sir now i got it. Now some other thing is confusing me, What happens electrons in transmission lines during power transmission.
    Are you sure? This action cannot be undone.
    Cancel

  • Ramani Aswath

    Member • May 2, 2014

    Same thing. Only lot mre electrons are involved. The branches of the distribution system also get into the act. Further in AC power transmission very high voltages are used to minimize line losses. At the use point transformers are used to step down voltages. There is no electron transfer between the primary and secondary of such transformers. The induced magnetic fields cause the secondary circuit electrons to oscillate.
    Are you sure? This action cannot be undone.
    Cancel

  • somuumos

    Member • May 2, 2014

    ok sir so the final conclusion is that electrons oscillate on their mean position with some frequency. Am I right sir.
    Are you sure? This action cannot be undone.
    Cancel

  • Ramani Aswath

    Member • May 3, 2014

    Yes. That is the way it is Somu forward and reverse. The same way your screen name is.
    You have to keep in mind the total length of the circuit. If the circuit is small and the frequency is low any specific electron may get lost. Even then, the number of electrons going in either direction for each half cycle will be equal.
    Are you sure? This action cannot be undone.
    Cancel

  • somuumos

    Member • May 3, 2014

    Thank you sir for your patience and care. i have got it clearly. i hope you will show the same interest for clearing my fore coming doubts.
    Regards
    Are you sure? This action cannot be undone.
    Cancel

  • Ramani Aswath

    Member • May 3, 2014

    Once a teacher always a teacher...
    Are you sure? This action cannot be undone.
    Cancel

  • Void Runner

    Member • May 10, 2014

    A.V.Ramani
    I am afraid that the statement that the same electron moves back and forth does not hold water.
    It depends. There are cases when this can happen. In glow discharge plasmas, it is not unusual to see this happen. You apply potential between 2 electrodes. Either of them can conduct and excite electrons for conduction via thermionic or field emission. So, when the potentials are reversed, it is very likely that the reverse process occurs. Under the laws of equilibrium, the system must constantly re-adjust itself to reach an equilibrium point. Generation and recombination of carriers are basically chemical processes that follow Le Chatelier principle.

    Practically, in an AC circuit, the electrons cannot move back and forth, because the distance between electrodes is too large and the frequency too high. But electron entering at one end = electron lost at other end and this process is reversed when the input is AC.
    Are you sure? This action cannot be undone.
    Cancel
Home Channels Search Login Register