Heat and Mass Transfer An electric cable of aluminium conductor (k = 240 W/mK) is to be insulated with rubber (k = 0.15 W/mK). The cable is to be located in air (h = 6 W/m²). The critical thickness of insulation will be 40 mm 800 mm 25 mm 160 mm 40 mm 800 mm 25 mm 160 mm ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Fourier's law of heat conduction is valid for Regular surfaces having non-uniform temperature gradients Two dimensional cases only Three dimensional cases only One dimensional cases only Regular surfaces having non-uniform temperature gradients Two dimensional cases only Three dimensional cases only One dimensional cases only ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer If the energy radiated per second per sq. cm. of the surface for wave lengths lying between λ, and λ + dλ is represented by (eλ.dλ), then eλ is called Absorptive power Emissive power Emissivity None of these Absorptive power Emissive power Emissivity None of these ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The product of Reynolds number and Prandtl number is known as Stanton number Biot number Grashoff number Peclet number Stanton number Biot number Grashoff number Peclet number ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Two balls of same material and finish have their diameters in the ratio of 2: 1 and both are heated to same temperature and allowed to cool by radiation. Rate of cooling by big ball as compared to smaller one will be in the ratio of 0.084027777777778 0.16736111111111 0.043055555555556 0.042361111111111 0.084027777777778 0.16736111111111 0.043055555555556 0.042361111111111 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer When heat is transferred by molecular collision, it is referred to as heat transfer by Conduction Radiation Scattering Convection Conduction Radiation Scattering Convection ANSWER DOWNLOAD EXAMIANS APP