Question Detail
Question
An electron is travelling at right angles to a uniform magnetic field of flux density 1.2 mT with a speed of 8×10⁶ m/s. Radius of circular path followed by electron is
Correct Answer
Option A is the correct answer.
Detailed Explanation
r = mv/(qB) = (9.11×10⁻³¹ × 8×10⁶)/(1.6×10⁻¹⁹ × 1.2×10⁻³) = (7.288×10⁻²⁴)/(1.92×10⁻²²) = 0.03796 m ≈ 3.8 cm.
Hint
r = mv/(qB).