Physics is 36 of the 180 MDCAT marks — 20% of the paper, and the section pre-medical students most often neglect. That neglect is understandable and expensive: a student aiming for a competitive aggregate cannot afford to write off a fifth of the exam.
The PMDC 2026 curriculum covers 16 units, and the balance differs from what FSc Physics teaching emphasises. Electricity and magnetism — current electricity, electromagnetism, electromagnetic induction, alternating current, electrostatics — is the largest cluster. Mechanics — motion, force, work and energy, circular motion, oscillations — is the foundation the rest rests on. Modern physics — atomic spectra, the dawn of modern physics, nuclear physics — is compact, heavily conceptual, and disproportionately worth revising because the question pool is narrow.
MDCAT Physics is not the same task as an FSc Physics paper. There are no long derivations and no multi-step numericals. Questions test whether you know which relationship applies and can apply it in one or two steps. A student who has memorised formulae without knowing when each one holds will answer confidently and incorrectly, because the distractors are built from exactly that error.
Every question below carries its answer and an explanation naming the principle involved, so you can identify whether a mistake was conceptual or arithmetic. Those two failure modes need different remedies.
40 free Physics MCQs with answers
When you miss a question, write down which principle you should have applied before checking the explanation. If you cannot name one, the gap is conceptual and belongs in the notes, not in more practice questions.
Alternating Current
Q1. In a purely resistive AC circuit, current and voltage are:
Answer: A — In a purely resistive circuit, no reactance exists, so current and voltage are in phase (phase difference = 0).
AC through Resistor, Capacitor, Inductor
Q2. The speed of electromagnetic waves in vacuum is:
Answer: B — All EM waves travel at c = 3 x 10^8 m/s in vacuum, regardless of frequency or wavelength.
Electromagnetic Waves Spectrum
Q3. The RMS value of AC voltage with peak value V0 is:
Answer: D — Vrms = V0/sqrt(2) = 0.707 V0. This is the equivalent DC voltage for same power dissipation.
Phase of AC
Atomic Spectra
Q4. Hydrogen line spectrum is produced when electrons transition from:
Answer: D — Emission line spectrum: electrons fall from higher (n2) to lower (n1) energy levels, emitting photons of specific wavelengths.
Atomic Spectra / Line Spectrum
Current Electricity
Q5. A battery of EMF 12 V and internal resistance 2 ohm is connected to 4 ohm external resistance. Terminal voltage is:
Answer: B — I = EMF/(R+r) = 12/6 = 2 A. V_terminal = EMF - Ir = 12 - 4 = 8 V.
Internal Resistance
Q6. A 60 W bulb is connected to 240 V supply. Current through it is:
Answer: A — P = VI => I = P/V = 60/240 = 0.25 A.
Maximum Power Output
Q7. A resistor has 12 V across it and 3 A through it. Its resistance is:
Answer: C — R = V/I = 12/3 = 4 ohm (Ohm's law).
Ohm's Law
Q8. A wire of length 2 m, cross-section 1 mm2 (1x10^-6 m2), resistivity 1.7x10^-8 ohm.m. Its resistance is:
Answer: D — R = rho L/A = 1.7x10^-8 x 2 / 1x10^-6 = 3.4x10^-8 / 10^-6 = 0.034 ohm.
Resistance and Resistivity
Q9. Electric current is defined as the rate of flow of:
Answer: C — I = ΔQ/Δt; current = charge passing per unit time, measured in amperes (A).
Steady Current
Dawn of Modern Physics
Q10. Planck's constant h has SI units of:
Answer: C — Planck's constant h = 6.626 x 10^-34 J.s. Energy of photon: E = hf.
Quantum Theory and Radiation
Electromagnetic Induction
Q11. Faraday's law states that induced EMF equals:
Answer: B — Faraday's law: EMF = -d(phi)/dt. Induced EMF equals the negative rate of change of magnetic flux.
Faraday's Law
Q12. Lenz's law states that the induced current flows to:
Answer: D — Lenz's law: induced current opposes the cause producing it (change in flux), consistent with energy conservation.
Lenz's Law
Q13. A step-up transformer has 100 primary and 500 secondary turns. Input 220 V. Output voltage is:
Answer: D — Vs/Vp = Ns/Np => Vs = 220 x (500/100) = 220 x 5 = 1100 V.
Transformer
Q14. A transformer operates on alternating current and not on steady direct current because it requires:
Answer: D — A steady current gives a constant flux; which induces nothing in the secondary. Alternating current continually changes the flux.
Transformers
Electromagnetism
Q15. The magnetic force on a charge moving parallel to the magnetic field is:
Answer: D — The force depends on the sine of the angle between velocity and field; when they are parallel that sine is zero and no force acts.
Force on a Moving Charge
Q16. Magnetic flux through area A in field B at angle theta to the normal is:
Answer: D — Magnetic flux phi = B.A = BA costheta, where theta is angle between B and area normal vector.
Magnetic Flux
Q17. The SI unit of magnetic flux density (B) is:
Answer: C — Magnetic flux density B is measured in Tesla (T). 1 T = 1 Wb/m2.
Magnetic Flux Density
Q18. A proton (m=1.67x10^-27 kg, q=1.6x10^-19 C) moves at 3x10^6 m/s perpendicular to B=0.5 T. Radius is:
Answer: D — r = mv/(qB) = 1.67x10^-27 x 3x10^6 / (1.6x10^-19 x 0.5) = 5.01x10^-21 / 8x10^-20 ≈ 0.0626 m.
Motion of Charged Particle in Magnetic Field
Electronics
Q19. A PN junction diode conducts easily when:
Answer: D — Forward bias reduces the potential barrier, allowing majority carriers to cross and significant current to flow.
PN Junction
Q20. The chief disadvantage of a half wave rectifier compared with a full wave circuit is its:
Answer: B — Half of every cycle is discarded; so the mean direct voltage is lower and the gaps between pulses make the ripple much harder to smooth.
Rectification
Q21. A half-wave rectifier uses:
Answer: A — Half-wave rectifier: a single diode passes only one half (positive or negative) of the AC cycle.
Rectification (Half and Full Wave)
Q22. Which quantity is unaffected by increasing the doping level on both sides of a pn junction?
Answer: B — Doping changes the junction geometry; the barrier height and the breakdown behaviour; but the electronic charge is a universal constant.
pn Junction and Diode
Electrostatics
Q23. The capacitance of a parallel plate capacitor increases if:
Answer: D — C = epsilon_0 epsilon_r A/d. Inserting a dielectric (epsilon_r > 1) increases capacitance.
Charging and Discharging Capacitor
Q24. Coulomb's constant k in SI units is approximately:
Answer: C — k = 1/(4pi epsilon_0) = 9 x 10^9 N.m2.C-2.
Coulomb's Law
Q25. The electric field at distance r from a point charge Q is:
Answer: D — E = kQ/r2. The field decreases as the inverse square of distance.
Electric Field
Q26. The electric field due to an infinite plane sheet of surface charge density σ is:
Answer: A — By Gauss's law, E = σ/2ε₀ on each side of an infinite sheet (E is uniform and independent of distance).
Electric Field (Infinite Sheet)
Q27. The electric field intensity at distance r from a point charge Q is:
Answer: A — E = kQ/r² (Coulomb's constant k = 1/4πε₀); field falls as inverse square of distance.
Electric Field Intensity (Point Charge)
Q28. Electric field lines originate from:
Answer: B — Electric field lines emerge from positive charges and terminate on negative charges.
Electric Field Lines
Q29. The electric potential at distance r from point charge Q is:
Answer: C — V = kQ/r. Potential falls as 1/r while field falls as 1/r2.
Electric Potential Energy and Potential
Fluid Dynamics
Q30. Bernoulli's equation is based on conservation of:
Answer: C — Bernoulli's equation is a statement of conservation of energy for flowing fluids.
Bernoulli's Equation
Q31. The equation of continuity states that for an incompressible fluid:
Answer: A — Equation of continuity: A1 v1 = A2 v2 (volume flow rate is constant).
Equation of Continuity
Q32. According to Stokes law, the drag force on a sphere of radius r moving with velocity v through a fluid of viscosity eta is:
Answer: A — Stokes law: F = 6 pi eta r v.
Fluid Drag
Q33. Flow is turbulent when Reynolds number is:
Answer: D — Flow becomes turbulent when Re > 2000 (approximately).
Fluid Flow (Laminar, Turbulent)
Q34. At terminal velocity, the net force on a falling body is:
Answer: A — At terminal velocity, weight = drag force, so net force is zero and acceleration is zero.
Terminal Velocity
Force and Motion
Q35. A car accelerates from 0 to 20 m/s in 4 s. The acceleration is:
Answer: D — a = dv/dt = (20-0)/4 = 5 m/s^2.
Acceleration
Q36. In a perfectly inelastic collision, which quantity is conserved?
Answer: A — In a perfectly inelastic collision, momentum is conserved but kinetic energy is not.
Collision (Elastic and Inelastic)
Q37. A person walks 3 km east and then 4 km north. The displacement is:
Answer: C — Displacement = sqrt(3^2 + 4^2) = sqrt(9+16) = 5 km.
Displacement
Q38. The slope of a displacement-time graph gives:
Answer: A — The slope of s-t graph = ds/dt = velocity.
Displacement-Time Graph
Q39. A 2 kg ball at 5 m/s collides and sticks to a stationary 3 kg ball. Their common velocity is:
Answer: C — Conservation of momentum: m1v1 = (m1+m2)v => 2x5 = 5v => v = 2 m/s.
Momentum and Explosive Forces
Q40. Newton's first law of motion is also called the law of:
Answer: D — Newton's first law states that a body maintains its state of rest or uniform motion unless acted upon by a force - this is the law of inertia.
Newton's Laws of Motion
Where to go next
These questions are a sample. The full Physics question bank is available in the topic-wise Physics practice tool, which lets you filter by chapter and tracks which questions you have already answered. If a question here exposed a gap, the MDCAT notes section covers the underlying theory chapter by chapter, and a full-length timed mock test is the best way to find out whether you can hold that accuracy under exam conditions.
Frequently asked questions
How many Physics questions are on the MDCAT 2026?
Physics accounts for 36 of the 180 MCQs — 20% of the paper.
Is MDCAT Physics harder than FSc Physics?
It is different rather than harder. The MDCAT removes long derivations and extended numericals, but demands faster recognition of which principle applies. Conceptual clarity matters more than computational stamina.
Which Physics topics should I revise last?
Modern physics — atomic spectra, nuclear physics, the dawn of modern physics — is the highest-yield late revision, because the question pool is small, largely conceptual, and quick to re-read.