An electron (m = 9.11 × 10?31 kg) has a speed of 0.50c. Determine the difference between its relativistic kinetic energy and the kinetic energy calculated without considering relativity.
A. 3.0 × 10?15 J
B. 2.0 × 10?15 J
C. 1.5 × 10?15 J
D. 2.4 × 10?15 J
E. 1.8 × 10?15 J
Answer: D
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