Heat Transfer

What do you mean by calorific value of fuel ?
Perhaps the highest temperature material you will ever see is the sun's outer atmosphere, or corona. At a temperature of about $$2 \times {10^6}$$  $$^oC$$ or $$3.6 \times {10^6}$$ $$ ^oF$$, the corona glows with a light that is literally unearthly. But because corona is also very thin, its light is rather faint. You can only see the corona during a total solar eclipse when the sun's disk is covered by the moon.
On increasing the temperature of a body, the frequency $$(f_{max})$$ corresponding to maximum emission of radiation will :
Convection is the process of transfer of heat in:
Which of the following is a physical change?