Electronics, semiconductors, electrons, Materials, Devices, and Simple Circuits.
Explore the fascinating world of Physics Electronics with Nokryan.com! This field forms the backbone of modern technology, integrating principles of semiconductors, electron dynamics, materials, and electronic devices. To do wonders in these Competitive exams i.e. ECAT a deep understanding of these principles is very fundamental.
Semiconductors and Their Role in Electronics
Semiconductors are materials whose conductivity lies between insulators and conductors and are very important in Physics Electronics. Electronic devices are based on the availability of diodes, transistors, integrated circuits, and electrolytic capacitors. The two most common semiconductors are silicon and germanium, which are the building blocks of microprocessors and many other electronic devices.
Electrons and Their Movement in Circuits
Electrons are the basic charge carriers that make the electricity flow in circuits. Current refers to the flow of electrons through conductive pathways, which is essential for electronic operations. Some knowledge of how electrons move through materials is critical to analyzing circuits, designing devices, and fault-finding electronics.
Materials in Physics Electronics
The choice of materials for electronic applications is made according to their properties such as electrical, thermal and mechanical. For instance, silicon wafers are great semiconductors and are thus used in microchips. Other specialized materials, including gallium arsenide and polymers, are used in high-performance and flexible electronics.
Electronic Devices and Simple Circuits
Diodes, transistors, capacitors, and other electronic devices constitute basic components of circuits. These devices control the flow of current, and power signals, and store electrical energy. In simple circuits, like p-n junction diodes, we observe the most blatant character of semiconductors: the flow of electric current resulting from the interaction between free-then-moving electrons and holes.
Depletion Region and Potential Barrier
In a p-n junction, a depletion region forms where electrons and holes recombine, creating a potential barrier. This barrier prevents further charge carrier movement unless an external voltage is applied. Silicon-based p-n junctions typically exhibit a potential barrier of 0.7V, whereas germanium-based junctions have a 0.3V barrier.
Physics Electronics MCQs for ECAT Preparation
For students preparing for ECAT, mastering Physics Electronics concepts through multiple-choice questions is essential. Nokryan.com provides a comprehensive set of MCQs covering semiconductors, electron behavior, material properties, and electronic circuit principles. These questions enhance conceptual understanding and problem-solving skills, ensuring better performance in entry tests.
Stay ahead in your ECAT preparation with Nokryan.com, your trusted source for high-quality physics MCQs and study materials.
Sample Test Mcqs Of Physics Electronics
1. A potential difference is developed across the depletion region of p-n junction due to ?
- Excess of protonscorrect
- Both A and B
- Negative ions
- Positive ions
- Excess of electrons
2. Crystal of germanium or silicon in its form at absolute zero acts as ?
- Both A and B
- A semiconductor
- An insulator
- Both A and Ccorrect
- A conductor
3. A potential barrier of 0.7V exists across p-n junction made from ?
- Gallium
- Arsenic
- Germanium
- Siliconcorrect
4. All the valence electrons present in a crystal of silicon are bound in the their orbits by ?
- Molecular bond
- Both A and B
- Both B and C
- Ironic bondcorrect
- Covalent bond
5. Computer chips are made from ?
- Strontium
- Aluminnium
- Siliconcorrect
- Helium
- Iron
6. The use of chips in electrons is described in the form of ?
- White boxes
- Orange boxescorrect
- Yellow boxes
- Black boxes
- Red boxes
7. Potential barrier across the p-n junction ?
- Starts further diffusion of electrons into p-regioncorrect
- Stops further diffusion of electrons into p-region
- All of these
- Stop further diffusion of electrons into n-region
8. The impurity in the germanium is usually in the ratio of ?
A = 1 : 10 4
B = 1 : 10 8
C = 1 : 10 12
D = 1 : 10 16
- B
- A
- C
- Dcorrect
9. Majority charge carriers in the break, it creates ?
- Electronscorrect
- Positrons
- Neutrons
- Holes
- None of these
10. In a p-n junction, the current flows due to ?
- Both A and Bcorrect
- Free electrons only
- Positrons only
- Both A and C
- Holes only
11. Whenever a covalent bond breaks, it creates ?
- An electron-hole pair
- An electron
- A positroncorrect
- A hole
12. Atomic number of germanium atom and number of valence electrons in if are respectively ?
- 22, 3
- 4, 32
- 32, 4
- 4,14
- 14, 4correct
13. In a p-n junction, the current flows due to ?
- Arsenic
- Germanium
- Gallium
- Siliconcorrect
14. In the forward biased situation, the current flowing across the p-n junction is a few ?
- Micro amperescorrect
- Pico amperes
- Amperes
- None of these
- Milli amperes
15. Depletion region contains ?
- Positive ions
- Protons
- Negative ions
- Both B and Ccorrect
16. Silicon is one of the most commonly used ?
- Semiconductorcorrect
- Both B and C
- Insulator
- Conductor
- Dielectric
17. The huge advances in electronics over the recent past are due to discovery and use of ?
- Semiconductors
- Heavy water
- Insulatorscorrect
- Iron
- Conductors
18. A p-type crystal is ?
- Pure crystal
- Neutral as a whole
- Impurity added crystalcorrect
- Both A and B
19. As a result of diffusion, a region is formed around the p-n junction which is a ?
- Negatively charged region
- Positively charges region
- Depletion regioncorrect
- Chargeless region
20. At room temperature, crystal of germanium in its pure form, act as ?
- A semiconductorcorrect
- None of these
- A conductor
- Both A and C
- An insulator
21. When phosphorus is added as an impurity in germanium, there is an increase in ?
- Holes in Ge
- Positrons in Ge
- Both A and Bcorrect
- Free electron in Ge
22. The external potential difference applied to p-n junction (made from germanium) in case of forward biased situation must be grater than ?
- 0.7 V
- 300 mV
- 0.3 Vcorrect
- 700 mV
- Both B and C
23. The external potential difference applied to p-n junction for forward biasing, supplies energy to ?
- Holes in n-region
- Both A and B
- Both A and C
- Free electrons in n-region
- Holes in p-regioncorrect
24. The potential barrier across the depletion region in case of silicon and germanium are respectively ?
- 0.3 V , 0.7 V
- 0.3 V , 0.1 Vcorrect
- 0.7 V , 0.3 V
- 0.7 V , 0.01 V
25. An outer most orbit represents stable configuration if it possesses ?
- 8 electrons
- No electron
- 4 electrons
- 16 electronscorrect
- 12 electrons