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Problem 2.28

10 November, 2015 - 10:38
This problem is a variation on Problem 2.11. Einstein found that the equation K=(1/2)mv^2 for kinetic energy was only a good approximation for speeds much less than the speed of light, c. At speeds comparable to the speed of light, the correct equation is K=\frac{\frac{1}{2}mv^2}{\sqrt{1-v^2/c^2}}
  1. As in the earlier, simpler problem, find the power dK/dt for an object accelerating at a steady rate, with v=at.
  2. Check that your answer has the right units.
  3. Verify that the power required becomes infinite in the limit as v approaches c, the speed of light. This means that no material object can go as fast as the speed of light. 

Solutions for chapter 2