Working principle of disappearing filament type optical pyrometer is based on the ________________?

A. Inside a pressure vessel
B. Of an object without coming in contact with it
C. Of liquid oxygen
D. Of moving objects at high temperature

A. Bellows
B. Diaphragm
C. Bourdon tube
D. U-tube

A. Greater safety of operation
B. Better quality of product
C. Greater operation economy
D. All A., B. and C.

A. Heat content of the system
B. Liquid volume in the tank
C. Flow rate
D. Level of liquid

A. Mercury in glass thermometer
B. Optical pyrometer
C. Iron-constantan thermocouple
D. Alcohol filled thermometer

A. Reducing value of Kc
B. Introducing integral control
C. Introducing derivative control
D. None of the above