Suppose that a photon emitted by a hydrogen atom with configuration 5d causes an electron to be dislodged from the surface of potassium, k metal. what are the minimum and maximum values possible for the de broglie wave length of an ejected electron? the work function for potassium, k metal is 3.67x10" j. (hint: which transitions in the h atom, starting from 1-5, produce a photon of sufficient energy to cause an electron to be ejected from the surface of potassium metal?

answerlinnaeus;

answer: semi-infinite solid initially at a uniform temperature of 400 ◦c is cooled at its surface by convection. the cooling fluid at a constant temperature of 200 ◦c has a convective coefficient (ha) of 250 w/m2.k. the physical properties of the solid: k = 20 w/m.k and α = 4 * 10-5  m2/s. using δx = 0.04 m and δt = 10 s. write the finite difference equations describing the transient heat transfer of the first five δx and the temperature profile after 30 s.