Seismometers choose one: a. measure vertical (up-and-down) ground motion but cannot measure horizontal (back-and-forth) motion. b. are only sensitive enough to record ground movements down to about 1 mm. c. can "feel" (or record) large earthquakes that happen on the opposite side of the world. d. begin recording when the ground shakes and surface waves arrive.

At what point the certain object feels zero garvitational force between earth and the moon. take the required information from the book.required: distance away from earth or moon

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

Acar traveling at 22 m/s starts to decelerate steadily. it comes to a complete stop in 15 seconds. what is it’s acceleration?