NTA Abhyas JEE Main2020PhysicsElectrostaticsPractice
You have a parallel plate capacitor, a spherical capacitor and a cylindrical capacitor. Each capacitor is charged by and then removed from the same battery. Consider the following situations (i) the separation between the plates of the parallel plate capacitor is reduced (ii) the radius of the outer spherical shell of the spherical capacitor is increased (iii) the radius of the outer cylinder of the cylindrical capac
Options
- AIn each of these situations (i), (ii) and (iii), charge on the given capacitor remains the same and potential
- BIn each of these situations (i), (ii) and (iii), charge on the given capacitor remains the same but potential
- CIn each of these situations (i), (ii) and (iii), charge on the given capacitor remains the same but potential
- DCharge on the capacitor in each situation changes. It increases in all these situations but potential differen
Correct answer
C. In each of these situations (i), (ii) and (iii), charge on the given capacitor remains the same but potential
Step-by-step solution
Each capacitor is charged and then removed from the battery. Changing the plate separation in a parallel plate capacitor or the radius of any shell or cylinder in the spherical or the cylindrical capacitors will not change the charge on any capacitor. Each capacitor, in the disconnected state, is an isolated system. In situation (i), since C = ε 0 A d , capacity will increase as d is reduced. Therefore, V = Q C   decreases, Q being the same. In situation (ii), C = 4 π ϵ 0 a b b - a = 4 π &