Problem 2.28

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,

. At speeds comparable to the speed of light, the correct equation is $K=\frac{\frac{1}{2}mv^2}{\sqrt{1-v^2/c^2}}$

As in the earlier, simpler problem, find the power for an object accelerating at a steady rate, with .
Check that your answer has the right units.
Verify that the power required becomes infinite in the limit as approaches , the speed of light. This means that no material object can go as fast as the speed of light.

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