Question

The capacity of a parallel plate condenser with air medium is C . If half of the space between the plates is filled with a slab of dielectric constant K as shown in the figure, then the capacity becomes :

• A. $\frac{K}{2}C$
• B. 2KC
• C. $\frac{(K+1)C}{2}$
• D. (K+1)C

Answer 1

The correct option is C $\frac{(K+1)C}{2}$

Capacity of a half parallel plate capacitor with air medium $=\frac{C}{2}$

Capacity of a half parallel plate capacitor with slab of dielectric constant K $=\frac{KC}{2}$

$\therefore$ Effective capacitance=capacity=$C_{eff}=\frac{KC}{2}+\frac{C}{2}=\frac{(K+1)C}{2}$