The temperature inside a furnace is usually measured by which of the following ?

A. Optical pyrometer
B. Mercury thermometer
C. Alcohol thermometer
D. Any of the above

Which of the following insulating materials was suitable for low temperature applications ?

A. Asbestos paper
B. Diatomaceous earth
C. 80 percent magnesia
D. Cork

The material of the heating element for a furnace should have___________?

A. Lower melting point
B. Higher temperature coefficient
C. High specific resistance
D. All of the above

In an electric room heat convector the method of heating used is______________?

A. Arc heating
B. Resistance heating
C. Induction heating
D. Dielectric heating

Induction furnaces are employed for which of the following ?

A. Heat treatment of castings
B. Heating of insulators
C. Melting aluminium
D. None of the above

Which of the following will happen if the thickness of refractory wall of furnace is increased ?

A. Heat loss through furnace wall will increase
B. Temperature inside the furnace will fall
C. temperature on the outer surface of furnace walls will drop
D. energy consumption will increase

A non-dimensional number generally associated with natural convection heat transfer is____________?

A. Prandtl number
B. Grashoff number
C. Pecelet number
D. Nusselt number

Induction heating process is based on which of the following principles ?

A. Thermal ion release principle
B. Nucleate heating principle
C. Resistance heating principle
D. Electro-magnetic induction princi¬ple

The process of heat transfer during the reentry of satellites and missiles, at very high speeds, into earth’s atmosphere is known as_______________?

A. Ablation
B. Radiation
C. Viscous dissipation
D. Irradiation

In resistance heating highest working temperature is obtained from heating elements made of_____________?

A. Nickel copper
B. Nichrome
C. Silicon carbide
D. Silver