De Broglie Waves: Questioning Accuracy?

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The discussion focuses on the accuracy of the non-relativistic calculation of the de Broglie wavelength for a 100-keV electron. The de Broglie wavelength is calculated using the formula λ = h/p, where p is the momentum derived from non-relativistic physics as p = mv. While non-relativistic calculations yield negligible errors at low speeds, significant deviations occur as particle speeds approach the speed of light due to relativistic effects. For a 100-keV electron, the speed is low enough that the percentage error in the de Broglie wavelength remains minimal. Ultimately, the accuracy of these calculations is contingent on the particle's energy and speed, necessitating relativistic considerations for higher energy scenarios.
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A Question of De Broglie Waves?

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The problem states: By what percentage willl a non-relativistic calculation of the de Broglie wavelength of a 100-keV electron be in error?
 
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The de Broglie wavelength of a particle is given by the equation λ = h/p, where h is Planck's constant and p is the momentum of the particle. In non-relativistic calculations, the momentum of a particle is given by p = mv, where m is the mass of the particle and v is its velocity.

To calculate the percentage error in the de Broglie wavelength, we need to compare the non-relativistic calculation with the relativistic calculation, which takes into account the effects of special relativity at high speeds.

At low speeds, the non-relativistic calculation is accurate and the percentage error is negligible. However, as the speed of the particle approaches the speed of light, the relativistic effects become significant and the non-relativistic calculation starts to deviate from the actual value.

In the case of a 100-keV electron, the speed is relatively low and the percentage error in the de Broglie wavelength would be very small. It is only at much higher energies, close to the speed of light, that the relativistic effects become significant and the non-relativistic calculation would result in a larger percentage error.

Therefore, while the non-relativistic calculation of the de Broglie wavelength may not be completely accurate, it is still a useful approximation for particles with low energies. For higher energy particles, a relativistic calculation would be more accurate. Overall, the accuracy of the de Broglie wavelength calculation depends on the energy and speed of the particle, and it is important to take into account the effects of special relativity at high energies.
 
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