A. Enhancement or attenuation of radiation occurs in the sighting path
B. Object and surrounding are at almost the same temperature
C. Object has varying emissivity
D. Object is transparent
Related Mcqs:
- Temperature of _____________ cannot be measured by an optical or radiation pyrometer?
A. Hot blast (air) from stoves
B. Molten slag flowing out of blast furnace
C. Combustion space in boilers
D. Rotary limestone calcination kiln - Starting temperature of optical radiation pyrometer is ______________ °C?
A. 800
B. 400
C. 1200
D. 1500 - Temperature measurement by optical pyrometer is done above ____________ point, which is 1063°C ?
A. Antimony
B. Gold
C. Silver
D. Nickel - Working principle of radiation pyrometer is based on the ________________?
A. Wien’s law
B. Kirchoff’s law
C. Stefan-Boltzmann law
D. Seebeck effect - Working principle of radiation pyrometer is based on the __________________?
A. Wien’s law
B. Kirchoff’s law
C. Stefan Boltzmann law
D. Seebeck effect - Operating range of a temperature measuring instrument is 800 to 1600°C. It could be a/an _____________ pyrometer?
A. Radiation
B. Optical
C. Photoelectric
D. None of these - Radiation thermometer cannot measure the temperature ___________________?
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 - Working principle of disappearing filament type optical pyrometer is based on the ________________?
A. Wien’s law
B. Seebeck effect
C. Kirchoff’s law
D. Peltier effect - Which of the following is a ‘contact’ pyrometer ?
A. Resistance pyrometer
B. Optical pyrometer
C. Radiation pyrometer
D. Infra red pyrometer - Which of the following is not classified as a thermo electric pyrometer ?
A. Resistance thermometer
B. Thermocouple
C. Optical pyrometer (disappearing filament type)
D. Radiation pyrometer
