1. Determine the mass (in kg and in Ibm) and the weight (N and lbf) of the air contained in a room whose dimensions are 6 mx 6 mx 8 m. Assume the density of the air is 1.16 kg/m3.
Knowing that the acceleration of gravity g=9.81 m/s = 62.2 ft2/s.

The temperature of air decreases as it is compressed by an adiabatic compressor. a)- true b)- false

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.

Afour cylinder four-stroke in-line engine has a stroke of 160mm, connecting rod length of 150mm, a reciprocating mass of 3kg and its firing order is 1-3-4-2. the spacing between cylinders is 100mm. i. show that the engine is in balance with regard to the primary inertia forces and primary 3. a and secondary inertia couples. li determine the out of balance secondary inertia force ii. propose ways of balancing this out of balance force and discuss the challenges that will arise