Capacitor with a dielectric: studying for an exam

AI Thread Summary
The discussion focuses on calculating the maximum energy stored in a parallel-plate capacitor with a dielectric constant of k=5.5, an area of 0.034 m², and a plate separation of 2 mm. The electric field must not exceed 200 kN/C to prevent damage. The user attempted to use the capacitance formula C = (ε0)A/d, substituting ε0 with ε0k for the dielectric. They also applied the energy formula U = 0.5CV², replacing V with E/d, but recognized that the electric field in a dielectric differs from that in free space. Understanding the impact of the dielectric on the electric field is crucial for accurate calculations.
mariexotoni
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Okay so I have a parallel-plate capactior
k=5.5
Area= .034m^2
Plate Separation= 2mm
If the Electric Field falls short, the capacitor will burn up if exceeding 200kN/C.

It's asking for the max energy stored by the capacitor.


My attempt was lame.
I tried using
C= (ε0)A/d

and since it's a dielectric, i replace ε0 with ε0k

Also I used
U= .5CV^2
Replacing V with E/d
 
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For a capacitor the field magnitude in a dielectric is not the same as the field magnitude in free space. So you might want to think a bit more about how the dielectric will affect things.
 

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