Electric field with dielectric constant

AI Thread Summary
The discussion focuses on calculating the electric field and charge of two electrodes with a Mylar dielectric between them. The charge before the Mylar is withdrawn is 62 pC, while after it is removed, the charge drops to 20 pC. The dielectric constant of Mylar is given as k=3.1, which affects the capacitance and electric field. The relationship between voltage, electric field, and distance is emphasized, indicating a uniform electric field between the plates. The user seeks assistance specifically with determining the electric field values before and after the Mylar is removed.
quietriot1006
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Homework Statement


Two 5.0mm*5.0mm electrodes with a 0.10mm thick sheet of Mylar between them are attached to a 9.0 V battery. Without disconnecting the battery, the Mylar is withdrawn. (Very small spacers keep the electrode separation unchanged.) Dielectric constant for Mylar is k=3.1. What is the charge before and after the Mylar is withdrawn?
What is the electric field before and after the mylar is withdrawn?

Homework Equations


C={k(epsilon_o)A}/d
Q=CV
C=kC_o


The Attempt at a Solution


I get the charges correctly but i just can't get the electric field before and after. Charge before is 62 pC and after its 20 pC. Help please.
 
Physics news on Phys.org
The electric field E is uniform between the two "plates". There is a simple relation between V, E, and the distance d between the plates.
 

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