Q. A metal foil of negligible thickness is introduced between two plates of a capacitor at the centre. The capacitance of capacitor will be
A) Same
B) Double
C) Half
D) $K$ times
Explanation
(a) The system will be equivalent to series combination of two capacitors of half thickness $ie.$,each of capacity 2 C
$\therefore\ \ \frac{1}{C_{s}} = \frac{1}{2c} + \frac{1}{2c} = \frac{1}{c}or\ C_{s} = c$
$\therefore$capacity remains the same
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.