99 Percentile Qs Bank for JEE MainPhysicsElectrostatics
Two concentric conducting spheres of radii r 1 and r 2 r 1  < r 2 carry electric charges of +   Q and - Q respectively. The region between the sphere is filled with two insulating layers of dielectric constant ε 1 and ε 2 and width d 1 and d 2 respectively. Variation of potential and electric field with radial distance from O is given. Select the correct one. (assume V a t   r 2 = 0
Correct answer
2
Step-by-step solution
Lets take value of Electric field in given regions as E 1 , E 2 , E 3   and   E 4 respectively. For r <    r 1 , net charge enclosed by the gaussian surface will be zero. ∴E 1 = 0 For r 1   <  r  <   r 1   +  d , from the concept of di-electrics we know that electric field in the presence of dielectric will be reduced by a factor equal to dielectric constant. ∴  E 2 = Q 4 πε 0 r 2 ε 1 Same way for r 1   +