The specific charge (e/m) of an electron was first measured by: MCQ with Answer and Explanation

The specific charge (e/m) of an electron was first measured by:
A. Thomson
B. Rutherford
C. Millikan
D. Bohr
Answer: Option A
Solution (By JKExamLibrary)
J. J. Thomson measured the specific charge (e/m) of electrons in 1897 using cathode ray tube experiments with electric and magnetic fields. Millikan later measured the charge e (oil drop experiment), allowing mass calculation. Rutherford discovered nucleus; Bohr developed atomic model. Memory aid: 'Thomson = e/m; Millikan = e'. This history-based question tests knowledge of experimental physics milestones, frequently appearing in competitive exams. Always link scientists to their specific measurements: Thomson (e/m), Millikan (e), Chadwick (neutron).

This question belongs to: Science Physics

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