a- A copper bar is 900 mm long and circular in section. It consists of 200 mm long bar of 40 mm diameter, 500 mm long bar of 15 mm diameter and 200 mm long bar of 30 mm diameter. If the bar is subjected to a tensile load of 60 kN, find the total extension of the bar. Take E for the bar material as 100 GPa.

The solid rod has a diameter of 20mm. Find the following: Angle of twist at C with respect to A (in radians) Angle of twist at B with respect to A (in radians) Maximum shear stress at A (in MPa) (Shear stress at support, at a point 7mm from center. (in MPa) A-36 steel with the following properties: Modulus of Elasticity, E = 29x10^3 ksi or 200 GPa Shear Modulus/Modulus of Rigidity, G = 11.5x10^3 ksi or 79.3 GPa Poisson's Ratio, nu = 0.260 Temperature Coefficient for thermal expansion, a = 6.6x10^-6/°F or 11.7x10^-6/°C

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Knowing that a 0.02in gap exists when the temperature is 75°F, determine (a) the temperature at which the normal stress in the aluminum bar will be equal to -11ksi, (b) the corresponding exact length (2 decimal places in 103 inches) of the aluminum bar. 0.02 in. 14 in. Bronze A = 2.4 in² E = 15 × 106 psi a = 12 x 10-6/°F 18 in. Aluminum A = 2.8 in² E = 10.6 × 106 psi a = 12.9 x 10-6/°F