A capacitor of 10 F capacitance whose plates are separated by 10 ~mm through air and each plate has area 4 ~cm ^2 is now filled equally with two dielectric media of K ₁=2, ~K ₂=3 respectively as shown in figure. If new force between the plates is 8 ~N . The supply voltage is _________ 10⁻⁴ ~V . (we modified language of question to make it correct)

Step-by-step solution

aligned & C _ eq = C ₁+ C ₂ & C ₁= 2 ₀ ~A 2 d =10 F & C ₂= 3 ₀ ~A 2 ~d =15 F & C _ eq =25 F aligned Now the charge on aligned & C ₁=10 ~V c & C ₂=1.5 ~V C . aligned Now force between the plates [F= Q^2 2 A ₀ ] aligned & 100 ~V ^2 10⁻¹² 2 2 10⁻⁴ ₀ + 225 ~V ^2 10⁻¹² 2 2 10⁻⁴ ₀ =8 & 325 ~V ^2=8 4 10⁻⁴ 8.85 & ~V ^2= 32 8.85 10⁻⁴ 325 & V = 283.2 10⁻⁴ 325 & ~V =0.93 10⁻² aligned