Aheat pump with refrigerant-134a as the working fluid is used to keep a space at 25
o
c by absorbing heat from geothermal water that enters the evaporator at 60
o
c at a rate of 0.065 kg/s and leaves at 40
o
c. refrigerant enters the evaporator at 12
o
c with a quality of 15% and leaves at the same pressure as saturated vapor.

if the compressor consumes 1.6 kw of power, determine

(a) the mass flow rate of the refrigerant,
(b) the rate of heat supply,
(c) the cop,
(d) the minimum power input to the compressor for the same rate of heat supply

What difference(s) did you notice using a pneumatic circuit over hydraulic circuit.explain why the pneumatic piston stumbles when it hits an obstacle.

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.

Thermal stresses are developed in a metal when its a) initial temperature is changed b) final temperature is changed c) density is changed d) thermal deformation is prevented e) expansion is prevented f) contraction is prevented