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PhysicsHardMCQ2025 · 22 Jan Shift 2

Q33.An electron projected perpendicular to a uniform magnetic field B moves in a circle. If Bohr's quantization is applicable, then the radius of the electronic orbit in the first excited state is : (1) √ πeeBh (2) √2hπeB (3) √ 2πeBh (4) √4πeBh

What This Question Tests

This multi-concept question combines the classical motion of a charged particle in a magnetic field with Bohr's quantization condition for angular momentum to determine the radius of the orbit.

Concepts Tested

Lorentz forceCentripetal forceBohr's quantization rule (angular momentum)Circular motion in magnetic field

Formulas Used

F_magnetic = qvB = mv^2/r

L = mvr = nh/2π

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