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Chemistry 2720 Fall 1999 Quiz 8 Solution

The rest energy is

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The kinetic energy is

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The total energy is therefore

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The momentum is found by

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The effective mass is

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The speed is therefore

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The classical calculation is much simpler:

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Classical mechanics gives a speed which is more than twice as large as relativity. This result is not just quantitatively wrong: Relativity theory tells us that no particle can be accelerated beyond the speed of light. (Try repeating the calculation with larger and larger kinetic energies if you need to convince yourself of this.) Classical mechanics does not and cannot predict this effect.



Marc Roussel
Tue Nov 30 09:01:58 MST 1999