# Mechanical Engineering:: Heat Transfer, Refrigeration and Air Conditioning

### Exercise

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#### Nusselt number (NN) is given by

 A. B. C D.

#### Which of the following represents a heat pump?

 A. B. C D.

#### The sensible heat factor during cooling and dehumidification process is given by (where h1= Enthalpy of air entering the cooling coil, h2+= Enthalpy of air leaving the cooling coil, and hA= Enthalpy of air at the end of dehumidification process)

 A. B. C D.

#### Reynolds number (RN) is given by (where h = Film coefficient, l = Linear dimension, V = Velocity of fluid, k = Thermal conductivity, t = Temperature, ρ= Density of fluid, cp = Specific heat at constant pressure, and μ= Coefficient of absolute viscosity)

 A. B. C D.

#### Fourier's law of heat conduction is (where Q = Amount of heat flow through the body in unit time, A = Surface area of heat flow, taken at right angles to the direction of heat flow, dT = Temperature difference on the two faces of the body, dx = Thickness of the body, through which the heat flows, taken along the direction of heat flow, and k = Thermal conductivity of the body)

 A. B. C D.

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