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Friday, 9 October

NEET UG 2025 · Physics · Question 18

NEET 2025 Physics, question 18

Question 18 of the NEET 2025 paper (code 45) is a Physics question from Moving Charges and Magnetism. Its idea, Charged Particle in a Magnetic Field, was asked twice, in 2019 and 2025, across NEET 2017–2026. The NTA final answer key gives option 2.

Updated 2026-10-08

Q18 · Physics

A model for quantized motion of an electron in a uniform magnetic field BB states that the flux passing through the orbit of the electron is n(h/e)n(h/e) where nn is an integer, hh is Planck's constant and ee is the magnitude of electron's charge. According to the model, the magnetic moment of an electron in its lowest energy state will be (mm is the mass of the electron)

  1. 1heπm\frac{he}{\pi m}
  2. 2he2πm\frac{he}{2\pi m}Official answer
  3. 3heBπm\frac{heB}{\pi m}
  4. 4heB2πm\frac{heB}{2\pi m}

Official answer: option 2 · NTA final answer key

Same idea

Charged Particle in a Magnetic Field, in other papers

NEET asked this idea twice, in 2019 and 2025. The other question below.

  • 2019 Q3Ionized hydrogen atoms and α-particles with same momenta enters perpendicular to a constant magnetic field, B. The ratio of their radii of…Numerical · Medium

Charged Particle in a Magnetic Field: every question and how it was framed

The chapter

Moving Charges and Magnetism in ten years of NEET

22 questions from 2017–2026, asked in 10 of 10 papers, about 2.1 a paper. Magnetic Force on Charges and Currents alone had 10.

Moving Charges and Magnetism: questions per paper

0242’172’182’191’204’213’222’231’243’252’26