a cube of glass of 5cm side and of mass 306g, has a cavity inside it. If the density of glass is 2.55gram per cubic centimetre, what is the volume of the cavity

electric field is a function of 1/r^2

yes, the force per unit charge for a point charge is inverse square law.

answer(20) psi;

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