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Course: Electromagnetism (Essentials) - Class 12th > Unit 7

Lesson 2: How to improve capacitors?
Science
Electromagnetism (Essentials) - Class 12th
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How to improve capacitors?
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Capacitors with dielectrics

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Problem

Mylar, a common dielectric used in capacitors, has a dielectric constant, K=3.1.
A thin strip of mylar is pasted on one of the plates of a capacitor, which changes the capacitance from its initial value, C0, to C.
The thickness of the dielectric strip (d/4) is a quarter of the plate separation of the capacitor (d).
If C0=10.3 μF, what is the new capacitance, C?
Note: The dielectric has the same area as the capacitor.
C=
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
  • an exact decimal, like 0.75
  • a multiple of pi, like 12 pi or 2/3 pi
μF