Thermal conductivity of water at 20°C is of the order of_____________________?

A. 0.1
B. 0.23
C. 0.42
D. 0.51

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

Thermal conductivity of air with rise in temperature__________________?

A. Increases
B. Decreases
C. Remains constant
D. May increase or decrease depending on temperature

Thermal conductivity of air at room temperature in kcal/m hr °C is of the order of__________________?

A. 0.002
B. 0.02
C. 0.01
D. 0.1

Cork is a good insulator because it has___________________?

A. Free electrons
B. Atoms colliding frequency
C. Low density
D. Porous body

Metals are good conductors of heat because________________?

A. Their atoms collide frequently
B. Their atoms-are relatively far apart
C. They contain free electrons
D. They have high density

Temperature of steam at around 540°C can be measured by ____________________?

A. Thermometer
B. Radiatiouv pyrometer
C. Thermistor
D. Thermocouple

Thermal conductivity of water in general with rise in temperature ____________________?

A. Increases
B. Decreases
C. Remains constant
D. May increase or decrease depending on temperature

Which of the following is a case of steady state heat transfer ___________________?

A. i.c. engine
B. air preheaters
C. heating of building in winter
D. all of the above

Which of the following is the case of heat transfer by radiation ___________________?

A. Blast furnace
B. Heating of building
C. Cooling of parts in furnace
D. Heat received by a person from fireplace