This document provides an overview of capacitors and inductors. It defines a capacitor as an electronic device that stores charge between two parallel plates, and an inductor as a passive component that stores energy in the form of a magnetic field. The document discusses how capacitors and inductors work, including how capacitors store charge and inductors store current. It also covers Faraday's law of capacitance, units of capacitance, types of capacitors and inductors, and how they combine in series and parallel.

1. Lecture # 1
Capacitors & Inductor
Lecture # 1
Capacitors & Inductor
By: Sarmad KhosaBy: Sarmad Khosa
Class of BS.IT, ISPClass of BS.IT, ISP
By: Sarmad KhosaBy: Sarmad Khosa
Class of BS.IT, ISPClass of BS.IT, ISP
Basic ElectronicsBasic Electronics

2. Capacitors
• Definition: A capacitor is an electronic device that stores
an electrical charge between the two plates
• A basic capacitor has two parallel plates separated by an
insulating material
• The unit of capacitance is Farads (F)
• Capacitance values are normally smaller, such as µF, nF
or pF

3. Different Types Of Capacitors

4. Reading Values of capacitance Of Capacitors

5. Storing a charge between the
plates
• Electrons on the left plate
are attracted toward the
positive terminal of the
voltage source
• This leaves an excess of
positively charged holes
• The electrons are pushed
toward the right plate
• Excess electrons leave a
negative charge
+
-
+ _+ _
Working Of Capacitors

6. Working Of Capacitors

7. What is dielectric?

8. The Farad Law and Unit of
Capacitance
• With more charging voltage, the electric field is stronger
and more charge is stored in the dielectric.
• Faraday Law: The amount of charge Q stored in the
capacitor is directly proportional to the applied voltage.
• Also, a larger capacitance can store more charge. These
relations are summarized by the formula:
Q =CV coulombs

9. Example
•How much charge is stored in a 2uF capacitor
connected across a 50-V supply?
Q =CV =(2u)x50
=100 uC
•A constant current of 2 uA charges a capacitor for 20 s.
How much charge is stored?
Q =Ixt
=2u x 2=40 uC

10. Example
•The voltage across the charged capacitor is 20 V from
previous example. Calculate C .
•A constant current of 5 mA charges a 10uF capacitor for
1 s. How much is the voltage across the capacitor?

11. Series and Parallel Combinations of
Capacitors
•Capacitors In series Capacitor In Parallel

12. Fixed And Variable Capacitors

13. Some Properties Of Capacitor
• In Capacitor, Current leads and voltage Lags.
• Allow AC current to pass.
• Stop DC current.
• Stores Voltage in the form of electric field.
• Capacitors in series:
1/Ct=1/C1+1/C2...
• Capacitor In Parallel:
Ct=C1+C2+C3...

14. Inductors

15. Inductors
• Definition: An inductor is a passive electronic component
that stores energy in the form of a magnetic field.
• In its simplest form, an inductor consists of a wire loop or
coil. The inductance is directly proportional to the number
of turns in the coil.
• Inductance also depends on the radius of the coil and on the
type of material around which the coil is wound.

16. Magnetism
• Any material possessing the property of magnetism is a
magnet.
• Every magnet has both a north (N) pole and a south (S)
pole.
• Just as “like” electric charges repel each other and “unlike”
charges attract, “like” magnetic poles repel each other and
“unlike” poles attract.

17. Magnetic Field In Current Carrying
Conductor
• A magnetic filed is associated with a moving charge.
• When current passes through a conductor, charges are
moving and so magnetic filed is created around it.

18. Magnetic Field In Current Carrying
Conductor

19. Magnetic Field In Current Carrying
Conductor

20. Working Of Inductor

21. Some Properties Of Inductor
• In Inductor, Current lags and voltage Leads.
• Allow DC current to pass.
• Stop AC current.
• Stores Current in the form of Magnetic field.