For the following beam assume concrete of compressive strength of 4,000 psi and density of 150 lbs/ft3 and reinforcing steel bars with yield strength of 75 ksi to a. examine if it cracks under its self weight b. if not, estimate the maximum load P, the beam can carry without cracking. c. If yes, estimate the minimum counteracting load (support) that needs to be provided in the middle of the span so that the beam does not crack.

Aloaded platform of total mass 500 kg is supported by a dashpot and by a set of springs of effective stiffness 72 kn/m. it is observed that when the platform is depressed through a distance x = 12.5 cm below its equilibrium position and then released without any initial velocity; it reaches its equilibrium position in the shortest possible time without overshoot. find the position and velocity of the loaded platform 0.10 sec. after its release. if a further load of 400 kg is added to the platform, find, i) the frequency of damped vibrations, and i) the amplitude of vibration after 2 complete oscillations, given that the initial amplitude is 15 cm.

Refrigerant 134a enters an insulated compressor operating at steady state as saturated vapor at -26°c with a volumetric flow rate of 0.18 m3/s. refrigerant exits at 9 bar, 70°c. changes in kinetic and potential energy from inlet to exit can be ignored. determine the volumetric flow rate at the exit, in m3/s, and the compressor power, in kw.

The proportional limit is always greater than the yield strength for a material. a)-trune b)- false