A 10 keV electron (mass = 9.1×10^-31 kg and charge = 1.6×10^-19 C) enters perpendicularly into the Earth's magnetic field (5×10^-5 T). Its Larmor radius is

UPSC Combined Geo-Scientist

Chemist

2 objective papers
120 questions each
2 h per paper
100 + 300 marks

Prelims Paper I covers general studies.

UPSC Combined Geo-Scientist, Prelims · 2025 · Paper I, General Studies · Q9 of 120

Geo-Scientist Prelims 2025 General Studies Q9: A 10 keV electron (mass = 9.1×10^-31 kg and charge = 1.6×10^-19 C)…

QuestionMagnetism / motion of charge

A 10 keV electron (mass = \(9.1\times10^{-31}\) kg and charge = \(1.6\times10^{-19}\) C) enters perpendicularly into the Earth's magnetic field (\(5\times10^{-5}\) T). Its Larmor radius is

(a) 5·93 km
(b) 5·93 m
(c) 6·75 km
(d) 6·75 m

Part of VKC Basic

Read the answer and its explanation with VKC Basic

VKC Basic (₹999 for 6 months) opens every solved answer, the notes, the handbook and the daily answer archive. Every Mains test series includes it.

See what is included Already a member? Sign in

Take this paper offlineAll 120 questions with answers and explanations in one PDF.

Download PDF Join Telegram