TP 30.46

          Given:   l = 0.320 nm

                        q = 175o

          

           Find: (a) l0 -?

 

Dl = l - l0 = h/(mec)(1-cos(q))

 

Dl =  (2.43 x 10-12 m)(1-cos(175o)) = 4.85 x 10-12 m

 

l0 = l - Dl =  0.320 nm - 0.00485 nm = 0.31515 nm

 

                     (b) E0, E - ?

 

E0 = hc/ l0

 

E0 = (1240nm-eV)/(0.31515 nm) = 3935 eV

 

E = hc/ l

 

E = (1240nm-eV)/(0.320 nm) = 3875 eV

 

                       (c) Ke - ?

Ke = E0 - E = 3935 eV – 3875 eV = 60.0 eV