A pair of wheels of a railway wagon carries a load of $2000$ kN on each axle box, acting at a distance of $600$ mm outside the wheelbase. The gauge of the rails is $2\mathrm{.}0$ m$\mathrm{.}\mathrm{}$

$1)$ Find the diameter of the axle between the wheels, considering allowable shear stresses to be $100$ MPa$\mathrm{.}\mathrm{}$

$2)$ If the shaft fails develop a corrective action $($define the cause for a problem and the design fixes$)$ for the problem and investigate$\mathrm{.}\mathrm{}$

$3)$ Research and explain modern design tools, processing, and analytical techniques available to design engineers.$\mathrm{}$

$4)$ If this solution is provided to Emirates Rail explain the need for proper design actions via discussions of current, newsworthy, design$-$related incidents.

A person places his hand palm downward on a scale and pushes down on the scale until it reads (8.12x10^1) N. The triceps muscle is responsible for this arm extension force. Find the force (in N) exerted by the triceps muscle. The bottom of the triceps muscle is 2.50 cm to the left of the elbow joint, and the palm is pushing at approximately 35.0 cm to the right of the elbow joint. (please ignore the number 96 shown in the scale). Give your answer with three significant figures. P 96.0 where P = 2.50 cm and Q = 35.0 cm.