Expectation Values in the Hydrogen Atom

28 Sketch the nodal surfaces (cones and planes) for the real 

30 Transform the expression for n I iy to Cartesian coordinates. Show that this function is an eigenfunction of the operator Ly and find its eigenvalue. 

31 Draw rough graphs of the following pairs of functions and argue from the graphs that the functions are orthogonal to each other  

32 Calculate the angle between the z axis and each of the cones of possible directions of the orbital angular momentum for 1 = 2. 

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