Top 1000+ Solved Heat Transfer (HT) MCQ Questions Answer
Q. Which dimensionless number correlates the relative thickness of the hydrodynamic and thermal boundary layers?
a. Mach number
b. 37,500 kg
c. Prandlt number
d. Nusselt number
e. Crash off number
Q. Prandtl number for gases is
a. more than 1000
b. 37,500 kg
c. near unity
d. between 100 and 1000
e. between 10 to 100
Q. Molecular transmission of heat is smallest in case of
a. Alloys
b. Solids
c. Liquids with impurities
d. Gases
e. Liquids
Q. Which one of the following will have least value of thermal conductivity?
a. Silver
b. Water
c. Glass
d. Air
e. Copper
Q. Which of the following property of air does not increase with rise in temperature?
a. Specific volume
b. Specific gravity
c. Thermal conductivity
d. Thermal diffusivity
e. Kinematic viscosity
Q. Entrainment separator is used in evaporators to
a. Reduce the boiling point
b. Increase the boiling point
c. Separate liquid droplets from vapour
d. Prevent foaming
e. Discharge mud and other impurities
Q. Which of the following can be used to measure a temperature around -50?C?
a. Platinum resistance thermometer
b. Thermocouple
c. Alcohol thermometer
d. Mercury thermometer
e. 37,500 kg
Q. The surface temperature of the sun is
a. 20000?K
b. 2000?K
c. 6000?K
d. Infinitely large
e. Millions of degrees
Q. What whould be shape of an ideal thermometer?
a. Spherical
b. Cylindrical
c. Cubical
d. Rectangular
e. None of the above
Q. Fouling factor
a. Measures the heat transfer efficiency
b. Is used only in case of Newtonian fluids
c. Is used when a liquid exchanges heat with a gas
d. Is dimensionless
e. Is virtually a factor of safety in heat exchanger design
Q. A dimensionless number representing the ratio of inertia forces to viscous forces is known as
a. Mach number
b. Prandtl number
c. Reynolds number
d. Nusselt number
e. Stanton number
Q. Thermal conductivity of wood least depends on
a. Moisture
b. Density
c. Temperature
d. Grain orientation
e. All of the above
Q. Heat is transferred from an insulated pipe to the surrounding still air mainly by
a. Free convection
b. Forced convection
c. All above together
d. Radiation
e. Conduction
Q. Dynamic similarity refers to the similarity of
a. 37,500 kg
b. temperature and heat flux
c. masses and forces
d. velocity and acceleration
e. physical dimensions