Choose the law that best describes the following statement: the volume of a gas is directly proportional to the number of moles of gas when temperature and pressure stay the same.
a. boyle's law
b. charles's law
c. avogadro's law
d. combined gas law

The precision of a laboratory instrument is ± 0.05 g. the accepted value for your measurement is 7.92 g. which measurements are in the accepted range? check all that apply. 7.85 g 7.89 g 7.91 g 7.97 g 7.99 g

Arefrigerator uses r-134a as the working fluid and operates on the ideal vapor-compression refrigeration cycle except for the compression process. the refrigerant enters the evaporator at 120 kpa with a quality of 34 percent and leaves the compressor at 70°c. if the compressor consumes 450 w of power, determine (a) the mass flow rate of the refrigerant, (b) the condenser pressure, and (c) the cop of the refrigerator. (0.00644 kg/s, 800 kpa, 2.03)

Wo small variable-thrust jets are actuated to keep the spacecraft angular velocity about the z-axis constant at ? 0 = 1.16 rad/s as the two telescoping booms are extended from r1 = 1.18 m to r2 = 4.69 m at a constant rate over a period of 124 seconds. the small 19-kg experiment modules at the ends of the booms may be treated as particles, and the mass of the rigid booms is negligible. determine the necessary thrust t for each jet as a function of time where t = 0 is the time when the telescoping action is begun. after you have the general expression for t, answer the questions. show work.