NEET 2026 question paper with answers | NEET Prep

Question 1

Two infinitely long parallel conducting wires A and B carry currents I and 2I, respectively, in the same direction. The wire A has uniform mass per unit length λ and lies on an insulated floor. The wire B is kept fixed at a height h above the floor. The minimum magnitude of h so that the wire A does not rise from the floor is: [g is the acceleration due to gravity and μ₀ is the permeability of free space.]

Accepted Answer

μ₀I²/(πλg). Parallel currents in the same direction attract, so wire B pulls A upward with a force per unit length μ₀(I)(2I)/(2πh) = μ₀I²/(πh). Wire A stays on the floor only while that does not exceed its weight per unit length λg, and the limiting case μ₀I²/(πh) = λg gives the minimum height h = μ₀I²/(πλg).

Answer

μ₀I²/(2πλg)

Answer

2μ₀I²/(πλg)

Answer

4μ₀I²/(πλg)

Question 2

In an adiabatic expansion, the temperature of one mole of an ideal monatomic gas (γ = 5/3) decreases from 60 K to 50 K. The work done by the gas in the process is: (Take the universal gas constant as R = 8.3 J mol⁻¹ K⁻¹)

Accepted Answer

124.5 J. No heat is exchanged in an adiabatic process, so the gas can only do work at the expense of its own internal energy: W = −nRΔT/(γ − 1). With ΔT = −10 K and γ − 1 = 2/3, W = −(1)(8.3)(−10) × 3/2 = 124.5 J, positive because the gas expanded.

Answer

41.5 J

Answer

83 J

Answer

166 J

Question 3

A photon and an electron, each of 20 eV energy, move in free space. The ratio of linear momentum of the electron pe to that of the photon pPh, that is pe/pPh, is: [Take speed of light = 3 × 10⁸ m s⁻¹, charge of electron = −1.6 × 10⁻¹⁹ C and mass of electron = 9 × 10⁻³¹ kg]

Accepted Answer

225. The two particles relate energy to momentum differently: a photon obeys p = E/c, while a non-relativistic electron obeys p = √(2mE). The ratio is therefore √(2mE) × c/E = c√(2m/E). With E = 20 eV = 3.2 × 10⁻¹⁸ J and m = 9 × 10⁻³¹ kg this evaluates to 225 — the electron carries far more momentum for the same energy.

Answer

2/450

Answer

1/250

Answer

275

NEET 2026

Q2.In an adiabatic expansion, the temperature of one mole of an ideal monatomic gas (γ = 5/3) decreases from 60 K to 50 K. The work done by the gas in the process is: (Take the universal gas constant as R = 8.3 J mol⁻¹ K⁻¹)

Q3.A photon and an electron, each of 20 eV energy, move in free space. The ratio of linear momentum of the electron pe to that of the photon pPh, that is pe/pPh, is: [Take speed of light = 3 × 10⁸ m s⁻¹, charge of electron = −1.6 × 10⁻¹⁹ C and mass of electron = 9 × 10⁻³¹ kg]