2.) For a 20‐mm‐diameter tube with either water or unused engine oil flowing through it, find: a.)The mean velocity, hydrodynamic entry length, and thermal entry length for each of the fluids with a temperature of 300 K if the mass flow rate is 0.01 kg/s. b.)The mass flow rate, hydrodynamic entry length, and thermal entry length for each fluid at 400 K and a mean velocity of 0.02 m/s.

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.

The higher the astm grain-size number, the coarser the grain is. a)-true b)-false

Burgers vector is generally parallel to the dislocation line. a)-true b)-false