1. a steel bar of circular section is subjected to uniaxial tension of load p. the original dimensions are given as diameter d0 and length 0 l . the reduction in diameter as a function of the loading p is approximated as 1 3 0 0 1 p d d p   = −     , and the extension of the bar is given as 1 3 0 0 1 p l l p   = +     when 0 p p = 0.05 , compute the ratio of true stress vs. engineering stress, i. e., true eng   and the true strain ( ) true  2. textbook problem 2.6a, b,c (see scanned copy)

Two technicians are discussing the intake air temperature (iat) sensor. technician a says that the computer uses the iat sensor as a backup to the engine coolant temperature (ect) sensor. technician b says that the powertrain control module (pcm) will subtract the calculated amount of fuel if the air measures hot. who is correct

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.

Fluids at rest possess no flow energy. a)- true b)- false