Question

why does potential diff /voltage [v] remains the same accross capacitors in series?

Answer 1

Dear Student,
Capacitors are said to be in series if charge on each individual capacitor is the same i.e. q₁= q₂ = q₃ = q
In this situation potential divides i.e. V = V₁+V₂+V₃

​Capacitors are said to be in parallel if potential across each individual capacitor is same and equal to the applied voltage one plate of all capacitors is connected to the positive terminal and the other plate of all capacitors to the negative terminal i.e.
V = V₁ = V₂ = V₃
In this situation charge distributes i.e.
q = q₁ + q₂ + q₃
​Regards