Question 1 Among the statements reported below, select the one that is false. O The heat conduction equation consists of an energy balance over an infinitesimal element domain. O The Fourier's law can be derived from the heat conduction equation. O The heat conduction equation is used in conjunction with boundary conditions and initial conditions, for defining the temperature field within a finite space domain. O Thermal conductivity is a property that (in reality) depends on temperature. Question 2 Consider the screen of a desktop as a 1D-plane wall model. When it is switched on, the steady-state temperature at the centre of the device will be (select the ONLY ONE true statement): O equal to the room temperature. O impossible to say. O higher than the room temperature. O equal to the temperature at the screen edges (which are exposed to the room). Question 3 Among the statements reported below, select the one that is false. O The heat transfer is a quantity always associated to a finite surface. O The heat flux is a vectorial quantity that can be evaluated at any point of the considered domain. O The mathematical expression for the temperature gradient is independent from the adopted coordinate system. O The temperature gradient in a point indicates the magnitude and direction of the biggest temperature variation around that point. Question 4 Consider an insulated pipe (2 layers). Please select the (ONLY ONE) true statement. O The heat flux is constant across the pipe thickness. O The total thermal resistance does not depend on the geometric properties of the pipe layers. O The heat transfer evaluated at the pipe innermost surface is equal to the one evaluated at the pipe outermost surface. O The surface of exchange at the innermost pipe radius is bigger than the one at the outermost radius.