Question

A parallel plate capacitor with air between the plates has a capacitance of 10f.what will be the capacitance, if the distance between the plates be reduced to half and the space between them is filled with a substance of dielectric constant 10

Answer 1

Hello,
here is your answer,
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old capacitance

C = (ε0A/d)

we know that the new capacitance will be

C' =  k(ε0A/d')

so,

C' ~ k/d'/

thus,

C'/C = (k/d') / (1/d)

= k(d/d')

here,

k = 10

and

d' = d/2

so,

C'/C = 10 x 2 (d/d)

or [as C = 10pF]

C' = 10pF x 20= 200pF

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Hope it helps u !!!

Cheers :))

# Nikky