Bsc/Msc Physics
Unit 1
Transistor
- Explain output and transfer characteristics of NPN/PNP transistor in common emitter (CE) mode.
- Explain construction and working of a JFET (Junction Field Effect Transistor). What are its parameters?
- Explain Types, construction, working and applications of a BJT (Bipolar Junction Transistor). What are its parameters?
- Disscus in details MOSFET and MESFET (types, working, and applications).
- What are I-V characteristics? Discuss the output I-V characteristics and supply voltage of different transistors (JFET , BJT , MOSFET, MESFET).
- Explain the working of different types of transistors and define the following: (i) Transconductance (gₘ) (ii) Drain resistance (r_d) (iii) Amplification factor (μ)
- What is the main principle of JFET/BJT/MOSFET/MESFET?
- What are the applications of transistors in circuit design?
- What is Gunn diode? Explain its construction, circuit diagram, working, application & advantage/disadvantages
Microwave Devices
- What are microwave devices? Discuss the principle and working of a Cavity Magnetron used in microwave generation.
- Explain the construction and operation of a Klystron amplifier. What are its applications?
- Describe the working principle of a Traveling Wave Tube (TWT) and compare it with the Klystron.
- What is a Gunn diode? Explain its working and applications in microwave devices.
- Explain the principle of operation of a Magnetron. What is its significance in radar technology?
Tunnel Diode
- What is a tunnel diode? Explain the phenomenon of quantum tunneling and how it contributes to the working of a tunnel diode.
- Discuss the construction, working principle, and applications of Tunnel Diodes in high-speed switching circuits.
- Derive the current-voltage characteristics of a tunnel diode and explain the negative resistance region.
- Compare the tunnel diode with a regular diode in terms of its characteristics and applications.
Transfer Electron Devices (TEDs)
- Explain the working principle of Transfer Electron Devices (TEDs). What role do they play in high-frequency applications?
- Describe the negative differential resistance phenomenon in TEDs. How does it contribute to their functionality?
- What are the different types of Transfer Electron Devices, and how are they used in microwave and millimeter-wave devices?
IMPATT Diode
- What is an IMPATT diode (Impact Ionization Avalanche Transit Time diode)? Explain its working and applications in microwave generation.
- Derive the current-voltage characteristics of an IMPATT diode and explain its behavior.
- Discuss the advantages and disadvantages of IMPATT diodes compared to other microwave devices.
Parametric Devices
- What are parametric devices? Explain the working principle of a Parametric Amplifier.
- Discuss the role of non-linearities in the functioning of parametric devices and their applications in communication systems.
- Describe the construction and operation of a parametric oscillator and its applications.
Avalanche Transit Time Devices
- What are Avalanche Transit Time (ATT) devices? Discuss their principle of operation and the negative resistance characteristics they exhibit.
- Explain the working of an ATR (Avalanche Transit Time) diode and its applications in high-frequency oscillators.
- Compare the performance of Avalanche Transit Time devices with other high-frequency devices like Gunn diodes and IMPATT diodes.
Unit 2
Photonic Devices & diode Lasers
- Explain radiative and non radiative transition in photonic Devices.
- Discuss construction and working of solar cell. Mention it's applications.
- What is the working principle of a Laser? Describe various properties of laser.
- What is light confinement factor?
- Obtain condition for population inversion in active region for diode lasers.
- Explain Light emitting diode LED and its Construction circuit, working, IV characteristics, high frequency limit and its applications.
- Explain the working of semiconductor diode lasers.
- Explain the working of LDR devices.
- Explain the working , principle, circuit diagram and applications of diode photo detectors in details.
- Explain optical gain and threshold current for lasing of diode lasers.
- What is optical absorption?
Unit 3
Memory & Storage devices
- What are the key differences between Read-Only Memory (ROM) and Random Access Memory (RAM)? Why do computers need both types of memory?
- Explain the different types of ROM —PROM, EPROM, EEPROM, and EAPROM. How do they work, and what makes them different from each other?
- How do Static RAM (SRAM) and Dynamic RAM (DRAM) store data? Compare their functions and where they are used.
- What are the main advantages and disadvantages of SRAM and DRAM in terms of speed, power consumption, and cost?
- What are hybrid memories? How do CMOS and NMOS memory technologies improve memory performance?
- What is Non-Volatile RAM (NVRAM)? How does it store data even when the power is turned off?
- What are ferroelectric memories? How are they different from traditional memory technologies, and where are they used?
- How do Charge-Coupled Devices (CCDs) work? What are their key applications, especially in imaging technology?
- How is data stored and organized in magnetic storage devices like floppy disks (FDD) and hard disk drives (HDD)?
- Explain how optical storage devices like CD-ROM, CD-R, CD-R/W, and DVD function. What makes them different from magnetic storage?
- Compare magnetic storage (like HDDs) and optical storage (like CDs and DVDs). What are the pros and cons of each?
- Describe the different types of ROM in detail. How do they store and erase data, and what are their real-world applications?
- How are SRAM and DRAM structured? Explain their working principles and compare their performance with diagrams.
- What are hybrid memories? How do CMOS and NMOS technologies improve memory efficiency? Compare their working principles and uses.
- What are Charge-Coupled Devices (CCDs)? Explain how they function, their structure, and their role in imaging and data storage.
- Discuss the different types of optical storage devices. How do CD-ROM, CD-R, CD-R/W, and DVDs differ in terms of capacity and usage?
- Explain the working of a Hard Disk Drive (HDD) with a diagram. How is data stored, organized, and accessed? What makes HDDs reliable for long-term storage?
Unit 4
Electro-Optic, Magneto-Optic, and Acousto-Optic Effects
- What is the electro-optic effect? How does it work, and what are its applications in modern technology?
- How does the magneto-optic effect work? Where is it used, particularly in optical storage and communication systems?
- Explain the acousto-optic effect with examples. How is it useful in laser-based applications?
- What material properties are necessary to achieve electro-optic, magneto-optic, and acousto-optic effects?
- What are ferroelectric materials, and how do they help in memory storage and electronic applications?
- How do liquid crystal materials work? Why are they so important in display technologies like LCD screens?
- What role do polymeric materials play in the development of optical and electronic devices?
- What are piezoelectric materials? How are they used in devices like sensors and actuators?
- Explain the electrostrictive and magnetostrictive effects. How do they contribute to modern technology?
- What are acoustic delay lines? How do they work, and where are they used?
- How do piezoelectric resonators and filters function? Why are they important in high-frequency electronic circuits?
- What are surface acoustic wave (SAW) devices? How are they used in telecommunications and signal processing?
- Explain in detail the electro-optic, magneto-optic, and acousto-optic effects. Why are they important in modern optical technologies?
- What are ferroelectric materials? Describe their structure, properties, and practical applications, especially in memory devices.
- How do piezoelectric, electrostrictive, and magnetostrictive materials work? Explain their real-world applications in sensors and actuators.
- What makes liquid crystals unique? Explain their role in display technologies like LCDs, along with their working principles.
- Discuss the concept of acoustic delay lines, piezoelectric resonators, and surface acoustic wave (SAW) devices. How do they help in telecommunications and high-frequency applications?