For particle To Remain undeflected Fe=−Fm⇒∣E∣=VBsinθE=100c×9×10−4sin90E=27×102 V/m and E=B×V
An electron (mass 9 × 10^-31 ~kg and charge 1.6 × 10^-19 C ) moving with speed / 100( = speed of light) is injected into a magnetic field B of…
NEET UG 2025 — Physics Electromagnetism
2025mcqmedium
An electron (mass 9×10−31 kg and charge 1.6×10−19C ) moving with speed c/100(c= speed of light) is injected into a magnetic field B of magnitude 9×10−4 T perpendicular to its direction of motion. We wish to apply an uniform electric field E together with the magnetic field so that the electron does not deflect from its path. Then (speed of light c=3×108 ms−1 )
Official previous-year question
Held on 30 Apr 2025 · Verified 9 Jul 2026.
Options
- A
E is perpendicular to B and its magnitude is 27×104 V m−1
- B
E is perpendicular to B and its magnitude is 27×102Vm−1
- C
E is parallel to B and its magnitude is 27×102 V m−1
- D
E is parallel to B and its magnitude is 27×104 V m−1
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