$2.$ A machine shaft, supported on angular contact ball bearing $\backslash ($ A $\backslash )$ and roller bearing at $\backslash ($ B $\backslash ),$ is shown in Fig $2.$ It is subjected to a radial force of $30$ kN and a thrust force of $8$ kN $.$ The thrust is taken by angular contact ball bearing A alone. The shaft rotates at $300$ rpm $.$ The expected life of the bearings is $4000$ h with $\backslash (90\backslash \%\backslash )$ reliability. The application factor is $1\mathrm{.}1.$ Select suitable bearings for the shaft. $($Use charts from Shigley$).$ Write down bore diameter, OD $,$ catalog $\backslash (\backslash$mathrm$\{$C$\}\_\{10\}\backslash )$ and $\backslash (\backslash$mathrm$\{$C$\}\_\{0\}\backslash )$ for selected bearings. Note: The shaft can be stepped; hence, the roller and angular contact bearings may have different bore diameters. $($Hint: Ex $11-7$ in Shigley book$)$

$(10$ marks$)$

Fig. $2$