The long horizontal metal plates are separated by 4mm. the lower plate is at a potential of -6V. What potential should be applied to the upper plate to create an electric field strength 4000v/m upwards in the sphere between the plates.

if the thermos has a vacuum innner, then heat through conv currents and conduction are reduced = vacuum flask

energy stored in the capacitor= 9.72 x 10⁻⁴ j

explanation:

the energy stored in the capacitor is given by

e= 1/2 c v²

e= energy stored

c= capacitance= 1.5 µc= 1.5 x 10⁻⁶f

v= potential difference=36 v

so energy stored= e= 1/2 (1.5 x 10⁻⁶) (36)²

energy stored= 9.72 x 10⁻⁴j