Afan is designed to last for a certain time before it will have to be replaced (planned obsolescence). the fan only has one speed (at a maximum of 700 rpm), and it reaches the speed in 5.0 s (starting from rest). it takes the fan 7.0 s for the blade to stop once it is turned off. the manufacturer specifies that the fan will operate up to 1 billion rotations. andre lives in a hot climate, works outside of the home from approximately 8: 00 am to 5: 00 pm, monday through friday, does not own an air conditioner, and can't sleep with the fan running. estimate how many hot days n hot andre will be able to use the fan, rounded to the nearest day.

Which is not a step in the rock cycle?

Consider the particle-in-a-box problem in 1d. a particle with mass m is confined to move freely between two hard walls situated at x = 0 and x = l. the potential energy function is given as (a) describe the boundary conditions that must be satisfied by the wavefunctions ψ(x) (such as energy eigenfunctions). (b) solve the schr¨odinger’s equation and by using the boundary conditions of part (a) find all energy eigenfunctions, ψn(x), and the corresponding energies, en. (c) what are the allowed values of the quantum number n above? how did you decide on that? (d) what is the de broglie wavelength for the ground state? (e) sketch a plot of the lowest 3 levels’ wavefunctions (ψn(x) vs x). don’t forget to mark the positions of the walls on the graphs. (f) in a transition between the energy levels above, which transition produces the longest wavelength λ for the emitted photon? what is the corresponding wavele

Which best represents the law of conservation of mass ?