PYQ Pattern Analysis: NEET History

NEET Question Distribution

Topic	Average Frequency	Question Type
Carnot efficiency calculation	1 question/year	Numerical — convert °C → K, then apply η = 1 − $T_{2}$ / $T_{1}$
Process identification / PV diagram	1 question/year	Conceptual — identify process type, compare slopes
Molecular speeds (v_rms, γ, DOF)	1 question/year	Numerical or conceptual — ratio calculations
First Law application	0–1 question/year	Sign convention and which term is zero

Classic NEET Traps by Year Pattern

Trap 1 — Celsius in Carnot (appears every 2 years): Temperatures given in °C; students forget to add 273. Wrong answer is always among the options. Method: always convert first.

Trap 2 — Adiabatic vs Isothermal confusion: Q: "In adiabatic expansion, temperature is constant." WRONG. Only isothermal keeps T constant; adiabatic changes T. Q = 0 ≠ $\Delta T$ = 0.

Trap 3 — Steeper curve identification: PV diagram shows two curves. Students must identify which is adiabatic (steeper). Adiabatic uses PV^γ (γ > 1) while isothermal uses PV = const.

Trap 4 — Speed ordering: "Which speed is the most probable on a Maxwell speed distribution?" → v_mp (the peak). "Which speed is largest?" → v_rms.

Trap 5 — DOF for polyatomic: $CO_{2}$ appears to be diatomic (C and $O_{2}$ ) but it is a polyatomic molecule with f = 6 (or sometimes treated as linear with f = 5). NEET typically uses f = 5 for linear polyatomic ( $CO_{2}$ ) and f = 6 for nonlinear ( $H_{2}O$ ). Always read the question.

High-Value Focus Areas for NEET 2026

Carnot efficiency with temperature conversion
Identifying adiabatic vs isothermal on PV diagram
v_rms calculation for a given gas at a given temperature
γ and specific heat values for monoatomic/diatomic