Refrigerant 134a flows at steady state through a horizontal tube having an inside diameter of 0.05 m. The refrigerant enters the tube with a quality of 0.3, temperature of 36°C, and velocity of 2 m/s. The refrigerant exits the tube at 9 bar as a saturated liquid. Determine:
(a) the mass flow rate of the refrigerant, in kg/s.
(b) the velocity of the refrigerant at the exit, in m/s.
(c) the rate of heat transfer, in kW, and its associated direction with respect to the refrigerant.

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.