Intro Quantum Course Fourier Analysis

jcnorman
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Homework Statement


Using ultra-short laser pulses, it is possible to probe the reaction dynamics of many chemical reactions, such as A+BC->(ABC)*->AB+C. This worksheet estimates some of the parameters necessary to do this.

(a) If the energy available to each final states species is roughly E~0.1eV, find the typical final velocities of the end products. Assume, for example, a molecule with atomic weight of 40. Show that these velocities are typically of the order v~.01A/fs where 1fs=10^-15s. If reactions cease to occur when the species are more than a few bond lengths away, say 2-4A, estimate the total time for such a chemical reaction in femtoseconds.

There are additional parts b-f, but I think if I can get a figured out, I might can manage the rest.

Homework Equations


I am not sure. The Fourier transform is probably relevant since that is the section indicated on the problem, but it may come up in a later part.

The Attempt at a Solution


I really have no idea where to start. If someone could point me in the right direction, I would greatly appreciate it.
 
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This looks like a relatively simple introduction to the question, not requiring Fourier transforms at this stage. How would you relate the energy of a species to its velocity?
 
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