Problem $2$:

In the lap joint on the right, six identical

rivets are used to connect the two plates. The

allowable shearing stress on the rivets is $60$ MPa ;

bearing stress between the rivet and the plate is

$150$ MPa ; and the normal stress on the plate is $90$

MPa $.$ The plates connected are $300$ mm wide and

$16$ mm thick. Also, the holes in the plates are $2\mathrm{.}5$

mm wider than the diameter of the rivets. a$)$

Determine the allowable diameter of the rivets

based on the given $3$ allowable stresses. What is

the safest rivet diameter to use?