What is the emissivity of a black body ?
Correct answer: B. 1
- A. 0
- B. 1
- C. 0.5
- D. 0.90
Explanation
A black body absorbs all incident radiation and emits the maximum possible radiation at a given temperature. Its emissivity is therefore defined as unity.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? support@testustad.com
Practise Heat Transfer Operations
645 free Heat Transfer Operations MCQs from Chemical Engineering, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Chemical Engineering questions like this
Chemical Engineering is on this paper prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for it.
More Heat Transfer Operations questions
Tubes are held between top and bottom tube sheets in Calandria type evaporator by keeping_________________?
What is the unit of thermal conductivity ?
Nusselt number is the ratio of the temperature gradient at the wall to_________________?
In SI units, thermal conductivity is expressed in__________________?
In pipe flow, heat is transferred from hot wall to the liquid by__________________?
Heat transfer rate described by Fourier's law will decrease, if the _____________ increases?