A solid steel bar 250 mm long is 10 mm square over part of its length, the remainder being circular with a diameter of 25 mm. A gradually applied tensile load P kN induces maximum stress in the bar of 200 MPa. The total strain energy in the bar when this stress of 200 MPa  is acting is 1,3 Joule. Take E = 200 GPa   Calculate : The load The length of the square portion of the bar The load that falls from a height of 8 mm and induces 1,3 Joules in the bar

2. An Aluminum-alloy block is loaded as shown in the figure. The application of this load produces a tensile strain of 500 x 10 at gage A. Calculate the magnitude of the applied load P. Let E = 100GPa 400mm 120 Gage A P 20mm

PROBLEM SOLVING: A rigid bar is supported by three non-rigid steel rods, as shown. Rods AB and FG are 0.8 m long with a cross-sectional diameter of 30 mm. Rod CDE is made up of equally-long 0.40 – m CD and DE whose cross-sectional diameters are 60 mm and 30 mm, respectively. A 45 kN downward load is applied to the rigid bar. There is no initial strain before the application of the load. Let Esteel = 200 GPa Determine the internal forces on rods AB, CDE, and FG Determine the displacement of the rigid bar. If the allowable displacement of the horizontal rigid bar is 0.071 mm downwards, what maximum allowable vertical load can be applied for a factor of safety of 3? А F 0.40 m 60mm¢ D 0.8 m 0.8 m 30mm¢ 30mmф 0.40 m 30mm E G 45 kN

The steel rails of a railroad are 12 m with a clearance of 3 mm at 15 oC. Calculate: 1.1 The change in temperature that will cause the rails to touch. 1.2 The stresses that would be induced at this new temperature if there were no initial clearance (E = 200 GPa and α = 12 × 10-6 /oC).