Category: Heat Transfer

A. emissivity
B. transmissivity
C. reflectivity
D. intensity of radiation
E. absorptivity

A. high thickness of insulation
B. high vapour pressure
C. less thermal conductivity insulator
D. a vapour seal
E. all of the above

A. glass
B. water
C. plastic
D. rubber
E. air

A. increases
B. decreases
C. remains constant
D. may increase or decrease depending on temperature
E. unpredictable

A. Wien’s law
B. Planck’s law
C. Stefan’s law
D. Fourier’s law
E. Kirchhoff’s law

A. at all temperatures
B. at one particular temperature
C. when system is under thermal equi-librium
D. at critical temperature
E. for a polished body

A. conduction
B. convection
C. radiation
D. conduction and convection
E. convection and radiation

A. m2/hr
B. m2/hr°C
C. kcal/m2 hr
D. kcal/m.hr°C
E. kcal/m2 hr°C

A. their atoms collide frequently
B. their atoms-are relatively far apart
C. they contain free electrons
D. they have high density
E. all of the above

A. cold water inlet and outlet
B. hot medium inlet and outlet
C. hot medium outlet and cold water inlet
D. hot medium outlet and cold water outlet
E. none of the above