872XXE

@872XXE@feddit.org

• ⁨Comment⁩ on ⁨What is negative voltage?⁩ ⁨⁨3⁩ ⁨days⁩ ago⁩:

  Well, this is correct.

• ⁨Comment⁩ on ⁨What is negative voltage?⁩ ⁨⁨4⁩ ⁨days⁩ ago⁩:

  Voltage is always a difference between two points. It is not absolute - it depends on where you measure from.

  When we measure voltage, we always choose a reference point (often called ground or 0 V).

  If a point has more electric potential than the reference → voltage is positive

  If a point has less electric potential than the reference → voltage is negative

  So, a voltage is “negative” only because of the chosen reference point.

  Example

  Imagine a battery:

  • the positive terminal is higher potential
  • the negative terminal is lower potential

  If you measure like this:

  • Red probe on +, black on − → +9 V
  • Red probe on −, black on + → −9 V

  Same battery, different reference → different sign!

  • Voltage is always relative
  • Negative voltage means: “This point is lower than the reference point”
  • The same physical voltage can appear positive or negative, depending on how you measure it