Applied Physics-1

Distinguish between spontaneous emission and stimulated emission of radiation.

Explain population inversion and the pumping mechanisms used to achieve it.

Identify and explain the roles of the active medium and resonant cavity in a laser.

Explain coherence and the key characteristics of laser light.

Describe the construction and working of a He-Ne laser.

Describe the construction and working of a fiber laser.

Explain the working principle of LiDAR and barcode readers as laser applications.

Explain how total internal reflection enables light propagation in optical fibers and define acceptance angle and numerical aperture.

Distinguish between single-mode vs multimode and step-index vs graded-index fibers, and explain the concept of attenuation.

Define the gradient of a scalar field and interpret it as the direction of steepest ascent.

Define the divergence of a vector field and interpret it as a measure of source or sink strength.

Define the curl of a a vector field and interpret it as a measure of local rotation or circulation.

State the Divergence Theorem and explain its physical meaning in relating a volume integral to a surface integral.

State Stokes' Theorem and explain its physical meaning in relating a surface integral to a line integral.

State Gauss's law for electricity in both integral and differential (point) form, explaining its physical significance.

State Gauss's law for magnetism, explaining why there are no magnetic monopoles.

State Faraday's law of induction in both integral and differential form, explaining how changing magnetic fields create electric fields.

State the Ampere-Maxwell law, explaining the role of displacement current in unifying electricity and magnetism.

Summarize the collective significance of Maxwell's equations in describing electromagnetic waves.

State de Broglie's hypothesis relating wavelength to the momentum of a particle.

Derive the expression for the de Broglie wavelength of an electron accelerated through a potential difference.

Explain the key properties of matter waves and how they differ from electromagnetic waves.

Define the wave function and explain its role in describing a quantum system.

Interpret the squared modulus of the wave function as a probability density (Born rule).

Explain the conditions for a physically valid wave function (single-valued, finite, continuous, and normalizable).

Explain why classical mechanics fails at the quantum scale, necessitating the Schrödinger equation.

State the time-dependent Schrödinger equation and explain the role of each term.

Explain how the time-independent Schrödinger equation is derived and under what conditions it applies.

Set up and solve the Schrödinger equation for a particle in a 1D infinite potential well (rigid box).

Derive the quantized energy levels for a particle in a 1D rigid box and explain their physical significance.

Explain the phenomenon of quantum mechanical tunneling and factors affecting tunneling probability.

Describe a physical application of quantum tunneling, such as in a scanning tunneling microscope.

Explain the superposition principle as a fundamental property of quantum systems.

Define a qubit as a two-level quantum system and explain how it uses superposition to differ from a classical bit.

Distinguish between fermions and bosons and state the Pauli exclusion principle.

Explain qualitatively how discrete atomic energy levels broaden into energy bands in a solid.

Describe the Fermi-Dirac distribution function and its relation to the Fermi level.

Distinguish between conductors, insulators, and semiconductors using band theory.

Explain the concept of doping and distinguish between intrinsic, n-type, and p-type semiconductors.

Explain how doping affects the position of the Fermi level in extrinsic semiconductors.