Answer:

Explanation:
Capacitance C is given by

A= area of capacitor cross section
d= distance
therefore,

A_1= πR^2
d_1= d

A_= π(2R)^2
d_2 = 2d

threfore

and

also we know that E= V/d
⇒
⇒
= A_1/A_2=
=4
therefore,

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