An electron is accelerated from rest through a potential difference of 50.0 kV. What is the speed of the electron? (c = 3.00 × 10⁸ m/s, e = 1.60 × 10^-19 C, mel = 9.11 × 10^-31 kg) A) 1.24 × 10⁸ m/s B) 1.33 × 10⁸ m/s C) 3.24 × 10⁸ m/s D) 3.33 × 10⁸m/s E) 4.12 × 10⁸ m/s

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Quizplus · Accepted Answer

The kinetic energy gained by the electron is equal to the work done on it by the electric field, which is eV. Using the equation $ \frac{1}{2}mv^2 = eV $, we can solve for v: $ v = \sqrt{\frac{2eV}{m}} $. Substituting the given values, $ v = \sqrt{\frac{2 \times 1.60 \times 10^{-19} \times 50.0 \times 10^3}{9.11 \times 10^{-31}}} \approx 1.24 \times 10^8 $ m/s.

An Electron Is Accelerated from Rest Through a Potential Difference