Relation between vaoltage, current, resistance and power

Inductors in parallel

Inductors in series

Capacitors in parallel

Capacitors in series

Resistors in parallel

Resistors are in series

Energy gap or band gap.

Energy gap or band gap.

-The difference in energy between the valence band and the conduction band is called an energy gap or band gap

-It is also called as forbidden gap

-  In semiconductors the band gap is smaller,

e.g

 1) Energy gap of silicon (Si) is 1.14 eV

2) Energy gap of Germanium is 0.67 eV

- For Insulators Energy gap is large 

- For conductor , no energy gap i.e overlapping valence and conduction band 

Summary of semiconductor, Conductor and Insulator

Summary of Insulator, Conductor and Semiconductor

Core - consists of all the inner shells and the nucleus.

Insulator -does not conduct electrical current under normal conditions.

                 -Very high resistivity

                - Very low conductivity

                - Bad conductors of elctricity.

        e.g. - rubber, glass, mica, quartz and plastics.

Conductor - conduct electrical current.

                     -Good conductors of electricity

                    - High conductivity

                    - Low resistivity

              e.g- copper, silver, gold, aluminium

Semiconductor –   Ability to conduct current between insulator and conductor

   -       neither a good conductor nor a good insulator

  -       Antimony, arsenic, astatine, boron, polonium, tellurium, silicon and germanium.

Basics concepts of electronics

• atom-smallest particle of an element
• nucleus- consist protons & neutrons 
• proton- positively charge particles
• neutrons- uncharged particles
• electrons - negatively charged particles
• simplest atom hydrogen - one proton & one electron
• atomic number- number of protons in the nucleus
• shells- orbits are grouped into energy levels 
• The Maximum Number of Electrons in Each Shell -Ne= 2n٨2
• valence shell- outermost shell
• valence electrons- electrons in the outermost shell
• mass-Protons and neutrons are approximately the same mass.
• mass of electron-1/1836 of a proton
• quarks - smaller particle within the protons and neutrons

Electronics MCQ

Q. Each atom in a silicon crystal has
a. four valence electrons
b. four conduction electrons
c. no valence electrons because all are shared with other atoms
d. eight valence electrons, four of its own and four shared

Q. Recombination is when
a. an electron falls into a hole
b. a positive and a negative ion bond together
c. a valence electron becomes a conduction electron
d. a crystal is formed

Q) Electron-hole pair are produced by
a. recombination
b. thermal energy
c. ionization 
d. doping

Q) The amount of AC content in the output of rectifier is called 
A) form factor
B) ripple factor
C) peak factor
D) Knee factor

Q) Due to forward bias voltage , width of depletion region
A) Enhances
B) Narrows
C) Remain same
D) None of the above

Q.) Barrier potential for silicon diode is
A) 0.3V
B) 0.4V
C) 0.1V
D) 0.7V

Q.) total current drawn from four 1.5V cells connected in series is 1 ampere. Each cell supplies 
1.) 1 A
2.) 0.25 A
3.) 1.5 A
4) 4 A

Q.) In an electronic circuit, common reference point is 
1.) always the negative battery terminal
2.) always the most positive point
3.) always the most negative point
4.) may be any point

Q.) The superposition theorem is based on 
1.) linearity
2.) Duality
3.) Reciprocity
4) Non-linearity