Question

BoNUs: Energy Storage Consider the capacitor as a device for storing energy. The practical limitation on the potential difference between the plates of a capacitor is the "dielectric strength" of the dielectric material between the plates. This is the maximum field strength that can exist without causing a spark. It is typically on the order of 107 v/m for a good liquid dielectric with K ะ 2.3 and ะ 1 g/cm3 (a) Neglecting the weight of the electrodes and case, what is the energy density of the capacitor in J/kg? Le., how many joules of energy can be stored per kilogram of dielectric? (b) The energy density of gasoline is about 46 MJ/kg, and gasoline has a density of about 0.75 g/cm3. Assume a gas tank holds about 12 gallons when full. What mass of dielectric would be required to provide the same energy as a tank of gasoline?

Answer 1