A parallel plate condenser has circular plates each of diameter 20 cm separated by a distance of 2 mm. The potential difference between the plates is maintained at 360 volt. Calculate its capacitance and charge. (k = 1)

T or F  A capacitor is a charge storage device whose capacitance is defined as the ratio of the amount of the potential difference (in volts) across its plates to the charge (in coulombs) on its plates.

When capacitor A holds a charge of 50C, the potential difference between its plates is 25 volts. When capacitor B holds a charge of 5 C, the potential difference between its plates is 0.1 volts. Which capacitor has the greatest capacitance?

A capacitor is constructed from two square, metallic plates of sides ℓ and separation d. Charges +Q and -Q are placed on the plates, and the power supply is then removed. A material of dielectric constant κ is inserted a distance x into the capacitor as shown in the figure below. Assume d is much smaller than x. Suggestion: The system can be considered as two capacitors connected in parallel. (Use the following as necessary: ε0, κ, ℓ, Q, d, and x.)   (a) Find the equivalent capacitance of the device.Ceq =     (b) Calculate the energy stored in the capacitor.U =

A parallel plate capacitor with a capacitance of 0.86 F with a has plate area A and are separated by a distance d. It is charged up to 11 V. The capacitor is now disconnected from the battery. If the area of the plates increases by a factor of 3 and the separation decreases by a factor of 10, find the new charge on the capacitor in Coulombs.

A potential difference of 75 mV exists between the inner and outer surfaces of a cell membrane. The inner surface is negative relative to the outer surface. How much work is required to eject a positive sodium ion (Na+) from the interior of the cell?

please answer v

A paper-filled capacitor is charged to a potential difference of Vo = 2.1 V. The dielectric constant of paper is K = 3.7. The capacitor is then disconnected from the charging circuit and the paper filling is withdrawn, allowing air to fill the gap between the plates. Find the new potential difference V of the capacitor. Vị = V While the capacitor is disconnected from the charging circuit, an unknown substance is inserted between the plates. The plates then attain a potential difference that is 0.47 times the original potential difference Vo (when paper filled the capacitor). What is this unknown substance's dielectric constant K? Ku =