
Assume initial separation as 3mm
each capacitance C1=3ϵ0A before
C1=3kϵ0A+2.4ϵ0A3kϵ0A.2.4ϵ0A
to get same capacitance 3ϵ0A=k3ϵ0A+2.4ϵ0Ak3ϵ0A.2.4ϵ0A
3k=2.4k+3
0.6k=3⇒k=0.63
k=630=5.
JEE Main 2017 — Physics Electromagnetism
A combination of parallel plate capacitors is maintained at a certain potential difference.

When a 3mm thick slab is introduced between all the plates, in order to maintain the same potential difference, the distance between the plates is increased by 2.4mm. Find the dielectric constant of the slab.
Held on 9 Apr 2017 · Verified 6 Jul 2026.
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