BCS Written Physics study guide
BCS Written Physics · Work through your exam, one topic at a time.
The BCS Written Physics examination is the subject-specific written paper taken by candidates who have cleared the preliminary screening and are competing for cadre posts through Bangladesh's Civil Service examination system. It is intended for physics graduates and others with a strong physical-science background who want a government career, and it rewards candidates who can reason in equations and explain physical ideas in clear prose rather than simply recall facts. The BCS Written Physics study guide has 9 sections and about 3,268 words.
01Mechanics
Mechanics questions rest on Newton's three laws, the impulse–momentum theorem, conservation of linear and angular momentum, work–energy relations, and rotational analogues of translational quantities. You should be fluent in resolving forces on inclines, handling tension in connected bodies, and applying the parallel-axis theorem for moments of inertia.
290 words, about 1 min02Gravitation and Fluid Dynamics
Gravitation covers Newton's inverse-square law, gravitational potential energy (–GMm/r), orbital velocity, escape velocity, and Kepler's three laws. Fluid dynamics adds pressure, Pascal's principle, Archimedes' buoyancy, continuity (A₁v₁ = A₂v₂), and Bernoulli's equation (P + ½ρv² + ρgh = constant).
237 words, about 1 min03Properties of Matter
This domain covers elasticity (stress, strain, Young's modulus, bulk and shear moduli, Poisson's ratio), Hooke's law and elastic potential energy, surface tension and capillarity, viscosity, and the behaviour of materials under load. You should understand the stress–strain curve: proportional limit, elastic limit, yield point, ultimate strength, and fracture, plus the difference between ductile and brittle materials.
257 words, about 1 min04Heat and Thermodynamics
Expect questions on the zeroth, first, and second laws, thermodynamic processes (isothermal, adiabatic, isobaric, isochoric), heat capacities (Cp vs Cv), latent heat, thermal conduction, and entropy. You must know the Carnot efficiency and the Kelvin–Planck and Clausius statements of the second law.
266 words, about 1 min05Waves
Wave questions require the wave equation v = fλ, superposition, standing waves, resonance in strings and pipes, beats, and the Doppler effect. You should understand transverse versus longitudinal waves, phase and path difference, and conditions for constructive and destructive interference.
248 words, about 1 min06Sound and Optics
Sound: speed in gases (v = √(γRT/M)), intensity and decibels, resonance, and the Doppler effect. Optics: reflection, refraction, Snell's law, total internal reflection, lenses and mirrors (1/f = 1/v + 1/u), magnification, interference (Young's double slit), diffraction gratings, and polarisation.
224 words, about 1 min07Electricity
Electrostatics (Coulomb's law, electric field, potential, capacitance), direct current circuits (Ohm's law, Kirchhoff's laws, series and parallel combinations, internal resistance, power), and basic circuit analysis. You should be comfortable computing equivalent resistance, using potential dividers, and understanding energy stored in a capacitor (½CV²).
215 words, about 1 min08Magnetism and Electromagnetism
Magnetic fields from currents (Biot–Savart, Ampère's law), force on a moving charge (F = qv × B) and on a current-carrying wire (F = BIL sinθ), electromagnetic induction (Faraday's and Lenz's laws), self and mutual inductance, and the behaviour of magnetic materials (dia-, para-, ferro-). You should also know the Lorentz force and motion of charged particles in magnetic fields.
253 words, about 1 min09Atomic, Nuclear and Particle Physics
Atomic models (Rutherford, Bohr), energy levels and spectra, the photoelectric effect, nuclear structure, radioactivity (alpha, beta, gamma), half-life, binding energy, mass defect, fission and fusion, and the standard model of particles (quarks, leptons, bosons). You should understand conservation laws in nuclear reactions: charge, nucleon number, energy, momentum.
1,278 words, about 6 min