A capacitor is formed from two concentric spherical conducting shells separated by vacuum. The inner sphere has radius 12.5 cm , and the outer sphere has radius 16.5 cm . A potential difference of 100 V is applied to the capacitor.(adsbygoogle = window.adsbygoogle || []).push({});

What is the energy density at r = 12.6 cm , just outside the inner sphere?

What is the energy density at r = 16.4 cm , just inside the outer sphere?

Equations:

U= 1/2 CV^2/Ad

U= 1/2 Eo E^2

C= EoA/d

V= Ed

C= 8.85*10^-12 *pi * .126^2/.04 =1.11*10^-11

so next i solved for U, U= .5 *1.11*10^-11 *100^2/pi*.126^2*.04=2.78*10^-5 which is not correct, Help PLease!

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# Homework Help: Capacitor with radius finding the energy density

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