why V(potential difference) remains same in parallel combination?

Hello,

Potential difference is measured as the difference in potential at two points.

So, when in parallel connection basically we measure potential difference between same two points for both the connections.

ex: Two wires for parallel connection will originate from a junction "A" and will end up in another junction "B". So for the both the wires the potential difference will be difference in potential at points A and B.

While in series the potential difference is measured between diffrent points and hence it can vary.

Regards,