Heat transfer MCQ with Answers

91) If the temperature of a solid surface changes form 27°C to 627°C, then its emissive power changes in the ratio of

Answer is:

81

92) Depending on the radiating properties, body will be transparent when

Answer is:

p = 0, T= l,anda = 0

93) A grey body is one whose absorptivity

Answer is:

does not vary with temperature and wave length of the incident ray

Explanation:

A grey body is defined as one whose absorptivity of a surface does not vary with temperature and wavelength of the incident radiation. In other words, if the ratio of emission of a body to that of a black body at a given temperature is constant for all wavelengths, then the body is called a grey body.

94) Which of the following is a case of steady state heat transfer

Answer is:

none of the above.

95) Total heat is the heat required to

Answer is:

91) If the temperature of a solid surface changes form 27°C to 627°C, then its emissive power changes in the ratio of

81

92) Depending on the radiating properties, body will be transparent when

p = 0, T= l,anda = 0

93) A grey body is one whose absorptivity

does not vary with temperature and wave length of the incident ray

94) Which of the following is a case of steady state heat transfer

none of the above.

95) Total heat is the heat required to

convert water into steam and superheat it