what conclusion does the student most likely make based
on this data?
is)
light waves always travel the same speed; however, the
speed of sound is determined by the medium that it
travels through
o all sound waves always have the same energy, so the
temperature of the medium does not affect wave speed.
o light needs to vibrate particles, so it travels fastest in
tightly packed solids, while sound does not need a
medium, so it travels fastest in a gas.
tightly packed particles in solids slow down the light
waves, however, sound waves make particles bounce
into each other, so they travel faster in solids.
which one?

Molten iron fills a mould, which has a volume of 200 cm cubed. calculate the volume when the iron cools and solidifies.

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

If 2 moles of co_2 at 2l and 500k are expanded reversibly to 20l, more work can be obtained from an adiabatic process than from an isothermal process. is the above statement true or false?