Heat conducted througfi unit area and unit thick face per unit time when temperature difference between opposite faces is unity,is called__________________?

Related Mcqs:

1. In heat exchangers, degree of approach is defined as the difference between temperatures of________________?

   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

2. According to Stefan’s law, the total radiation from a black body per second per unit area is proportional to____________________?

   A. absolute temperature
   B. T2
   C. T5
   D. t
   E. l/T

3. Log mean temperature difference in case of counter flow compared to parallel flow will be________________?

   A. same
   B. more
   C. less
   D. depends on other factors
   E. none of the above

4. When heat is transferred form hot body to cold body, in a straight line, without affecting the intervening medium, it is referred as heat transfer by __________________?

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

5. When heat is Transferred by molecular collision, it is referred to as heat transfer by __________________?

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

6. When heat is transferred from one particle of hot body to another by actual motion of the heated particles, it is referred to as heat transfer by ___________________?

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

7. Sensible heat is the heat required to __________________?

   A. change vapour into liquid
   B. change liquid into vapour
   C. increase the temperature of a liquid of vapour
   D. convert water into steam and superheat it
   E. convert saturated steam into dry steam

8. Total heat is the heat required to__________________?

   A. change vapour into liquid
   B. change liquid into vapour
   C. increase the temperature of a liquid or vapour
   D. convert water into steam and superheat it
   E. convert saturated steam into dry steam

9. LMTD in case of counter flow heat exchanger as compared-to parallel flow heat exchanger is _________________?

   A. higher
   B. lower
   C. same
   D. depends on the area of heat exchanger
   E. depends on temperature conditions

10. In regenerator type heat exchanger, heat transfer takes place by___________________?

    A. direct mixing of hot and cold fluids
    B. a complete separation between hot and cold fluids
    C. flow of hot and cold fluids alternately over a surface
    D. generation of heat again and again
    E. indirect transfer