: Chất lỏng có khối lượng riêng  = 850 kg/m3, chảy theo ống dẫn với lưu lượng Q = 20 l/s . Tại một tiết diện ống có đường kính trong d1 = 30 cm và áp suất p1= 11at ; Tại một tiết diện khác đặt thấp hơn tiết diện trên một khoảng là h thì ống có đường kính trong d2 = 25cm và áp suất p2 = 10 at. Hãy tính khoảng cách giữa hai tiết diện ống ( h ).

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

Abanked road comer of radius 146 m is to be constructed. if the comer is designed for vehicles moving with a speed of 20.0 m/s, what should the banking angle be, in units of degrees?

Which situation will have the highest resistance? a.long wire and high temperatureb.short wire and high temperaturec.long wire and cold temperaturedshort wire and low temperature