Arefrigerator uses refrigerant-134a as the working fluid and operates on an ideal vapor-compression refrigeration cycle between 0.14 and 0.8 mpa. if the mass flow rate of the refrigerant is 0.05 kg/s, determine (a) the rate of heat removal from the refrigerated space and the power input to the compressor, (b) the rate of heat rejection to the environment, and (c) the cop of the refrigerator.

(a) The rate of heat removal from the refrigerated space is 10.06KJ/s and the power input to the compressor is 7.57KJ/s

(b) The rate of heat rejection to the environment is 2.49KJ/s

(c) The COP of the refrigerator is 1.33

Explanation:

Mass flow rate of refrigerant = 0.05kg/s

From the steam table, enthalpies of the saturated liquid and vapor refrigerant at 0.14MPa and 0.8MPa are

0.14MPa: hf = 59.3KJ/kg, hg = 1410.4KJ/kg

0.8MPa: hf = 260.4KJ/kg, hg = 1460.2KJ/kg

(a) Rate of heat removal from the refrigerated space = 0.05(260.4 - 59.3) = 10.06KJ/s

Power input to the compressor = 10.06 - 2.49 = 7.57KJ/s

(b) Rate of rejection of heat to the environment = 0.05(1460.2 - 1410.4) = 2.49KJ/s

(c) COP of the refrigerator = 10.06 ÷ 7.57 = 1.33

show the wavelengths of a wave. show the crests of a wave.

  the unit of the measure =

explanation:

  the property that is quantified by the energy needed per of material to raise the temperature by one.

  si unit of energy = joule (j)

  si unit of temperature = kelvin (k)

  si unit of mass of material = kilogram (kg)

the property that is quantified by the energy needed per of material to raise the temperature by one is called specific heat.

the unit of specific heat is