Chapter 06 Electromagnetic Field Theory

1. EMT Presentation
PARALLEL PLATE CAPACITANCE

2. Made By:
 Raj Kumar
 BE-Electrical Engineering
 Sukkur IBA University
 Main Campus Sukkur

3. Capacitance
 Capacitance is the ability of a body to store an electrical charge. Any object
that can be electrically charged exhibits capacitance. A common form of
energy storage device is a parallel-plate capacitor.
 A capacitor is a device for storing electrical charge. Capacitors consist of a
pair of conducting plates separated by an insulating material (oil, paper,
air).
 The measure of the extent to which a capacitor can store charge is called
Capacitance.
 https://www.youtube.com/watch?v=f_MZNsEqyQw

4. Factors Affecting Capacitance
 The capacitance is only a function of the physical dimensions (geometry)
of the conductors and the permittivity of the dielectric. There are three
basic factors of capacitor construction determining the amount of
capacitance created.
 C is the capacitance
 A is the area of overlap of the two plates;
 εr is the relative permittivity of the material between plates ε0 is the
electric constant (ε0 ≈ 8.854×10−12 F m–1); and d is the separation
between the plates

5. Capacitance Area

6. Dielectric

7. Dielectric

8. Linear Dielectric

9. Capacitance
 Let two Conductors M1 and M2 are embedded in a homogenous dielectric
material
 M2 is positively charged
 M1 is negatively charged
 Both of Conductors are Equipotential Surface
 Electric flux is directed from M2 to M1 because M2 is at more positive
potential between two conductors
 The Ratio of the charges per potential difference is known as capacitance
 C=Q/V

10. Capacitance
 Where
 Q is the number of charges
 C is the Capacitance
 V is the Potential Difference b/w M1 and M2
 The same concept is for the summation
of the charges like the integration we have
the rule
C=∫s €.E/ ∫ E.dL

11. Parallel Plate Capacitors
 By applying the definition of Capacitance to a Simple Two conductor
systems which are identical, infinite parallel planes with separate d.
 There are two boundaries
 Lower
 Upper

12. Parallel Plate Capacitors
 Final Equation for the Parallel Plate Capacitors

13. Parallel Plate Capacitors

14. Example

15. Dielectric Material

16. THANKS