Problem Solving Modern Physics
Concepts to remember on Problemsolving in Modern Physics for JEE and CBSE board exams:
Quantum mechanics:

Key concepts:
 Waveparticle duality, principle of complementarity.
 Schrodinger’s wave equation, interpretation of wave function, probability distribution, boundary conditions.
 Quantum states and operators.
 The uncertainty principle.
 Quantum tunneling, the potential barrier, applications.

Handy phrases/Mnemonics:
 Waveparticle duality: “Sometimes a wave, sometimes a particle, quantum weirdness is quite hard to articulate”
 Schrödinger’s equation: “Ψ describes the wavelike state, solving this equation reveals quantum fate.”
 Uncertainty principle: “Position and momentum, you cannot know both, the more you know one, the more the other is lost.”
Atomic physics:

Key concepts:
 Quantum numbers, atomic orbitals.
 Aufbau principle, Pauli exclusion principle, Hund’s rule.
 Electronic configurations, periodic properties.
 Ionization energy, electron affinity, electronegativity.

Handy phrases/Mnemonics:
 Quantum numbers: “n for energy levels, l for angular momentum, ml for orientation, and ms for spin, remember them all, to quantum chemistry, you’ll win.”
 Aufbau principle: “Electrons fill orbitals, from low energy to high, following this rule, you won’t go awry.”
 Pauli exclusion principle: “No two electrons can share the same quantum state, this is the rule that makes atoms great.”
Nuclear physics:

Key concepts:
 Nuclear structure, isotopes, isobars, isotones.
 Nuclear forces, binding energy, mass defect.
 Nuclear reactions, fission, fusion, chain reactions, nuclear power.
 Radioactive decay, halflife, types of decay.

Handy phrases/Mnemonics:
 Nuclear structure: “Protons and neutrons, densely packed, give atoms their weight, that’s a nuclear fact.”
 Nuclear reactions: “Fission splits big, fusion combines small, chain reactions multiply, nuclear power lights it all.”
 Radioactive decay: “Atoms can be unstable, emitting radiation, their halflives determine their transformation station.”
Relativity:

Key concepts:
 Galilean relativity, the principle of relativity, inertial frames.
 Special relativity, time dilation, length contraction.
 Massenergy equivalence, Einstein’s massenergy relation.
 General relativity, the equivalence of mass and gravity, gravitational waves.

Handy phrases/Mnemonics:
 Galilean relativity: “Laws of motion, all the same, in moving frames, no one feels the blame.”
 Special relativity: “Time stretches, lengths shrink, as we approach light speed, relativity reveals, this unique deed.”
 General relativity: “Mass bends spacetime, gravity’s might, general relativity brings it to light.”
Applications of modern physics:

Key concepts:
 Quantum mechanics in electronics, the transistor.
 Nuclear energy and nuclear power plants.
 Radioisotopes and their applications in medicine and industry.
 Laser technology, holograms, and optical communication.
 Particle accelerators and the search for fundamental particles.
 Quantum computing and quantum information processing.

Handy phrases/Mnemonics:
 Quantum mechanics in electronics: “Transistors, the heart of electronics, quantum tunneling’s the key, to their fantastic tricks.”
 Nuclear energy: “Nuclear power, energy immense, fission and fusion, release the potential hence.”
 Radioisotopes: “Radioactive isotopes, in medicine and industry, trace, diagnose, heal, their uses can’t be unseen.”