Water (Prandtl number ?6) flows over a flat plate which is heated over the entire length. Which one of the following relationship between the hydrodynamic boundary layer thickness (?) and the thermal boundary layer thickness (?)t is true?

What is the equivalent emissivity for radiant heat exchange between a small body (emissivity = 0.4) in a very large enclosure (emissivity = 0.5)?

If a body is at 2000K, the wavelength at which the body emits maximum amount of radiation is __________

Which of the following parameter is not responsible for loss of heat from a hot surface in room?

Hot coffee in a cup is allowed to cool. Its cooling rate is measured and found to be greater than the value calculated by conduction, convection and radiation measurement. The difference is due to:

Which of the following statement is incorrect?

A periodic type heat exchanger is known as _____

Surface heat exchangers are also known as _______

In which type of heat exchanger the same space is occupied by the hot and cold gases, between which heat is exchanged?

Which of the following is not an application of regenerator?

What property of cold fluid remains constant in case of evaporator?