MHT CET202211 Aug 2022Morning ShiftPhysicsCapacitanceActual
In a parallel plate air capacitor of plate separation d , a dielectric slab of thickness t is introduced between the plates (t < d) . The capacitance becomes one-third of the original value. The dielectric constant of the slab will be
Options
- At 2 d+t
- Bt d-2 t
- Ct d+t
- D2 t 2 d-t
Correct answer
A. t 2 d+t
Step-by-step solution
Equivalent Capacitance of the dielectric-air system is given by 1 C^ = ( d-t ₀ A )+ ( t K ₀ A )= d-t (1- 1 K ) ₀ A If new capacitance is given by one third of the old value: aligned & C= ₀ A d-t (1- 1 K ) = ₀ A 3 d & d-t+ t K =3 d & K= t 2 d+t aligned