A. Admiralty brass
B. Stainless steel
C. Aluminium brass
D. Titanium
Related Mcqs:
- A furnace is made of a refractory brick wall of thickness 0.5 metre and thermal conductivity 0.7 W/m.°K For the same temperature drop and heat loss, this refractory wall can be replaced by a layer of diatomaceous earth of thermal conductivity 0.14 W/m.K and thickness ______________ metre?
A. 0.01
B. 0.1
C. 0.25
D. 0.5 - Thermal diffusivity of a substance is proportional to (where, k = Thermal conductivity) ____________________?
A. 1/k
B. k
C. k2
D. 1/k2 - Which of the following materials has the poorest electrical conductivity ?
A. Carbon
B. Aluminium
C. Silver
D. Stainless steel - One face of a furnace wall is at 1030°C and the other face is exposed to room temperature (30°C). If the thermal conductivity of furnace wall is 3 W. m-1. k-1 and the wall thickness is 0.3 m, the maximum heat loss (in W/m) is____________________?
A. 100
B. 900
C. 9000
D. 10000 - Thermal conductivity of a material does not depend upon its_____________________?
A. Mass
B. Volume
C. Surface area
D. All A, C & C - What is the critical radius of insulation (cms) for a metallic cylinder, if the convective heat transfer co-efficient with the ambient atmosphere is 5 W/m2. °K? Thermal conductivity of metal and insulation material are 40 and 0.1 W/m.°K respectively ?
A. 2
B. 8
C. 10
D. 40 - The ratio of thermal & electrical conductivity is same for all the metals at the same temperature; and at around room temperature, this ratio is proportional to(where, T = absolute temperature, °K) ?
A. T
B. 1/T
C. T2
D. 1/T2 - In condensers used in thermal power plants, steam is normally used in shell side and cooling water on the tube side, because of the reason that ?
A. Compared to the mass flow rate of cooling water, the rate of condensation of steam is
invariably smaller
B. Maintaining vacuum on tube side is more difficult than that on the shell side
C. Water velocity can be increased conveniently to increase the overall heat transfer co-efficient
because of its lower specific volume compared to steam
D. Condenser can act as a storage unit for condensed steam - Temperature of hot gases flowing in a pipe is measured by a thermocouple inserted in the thermal well. The thermal well made of ______________ will facilitate the most accurate measurement of the temperature ?
A. Copper
B. Steel
C. Aluminium
D. Brass - A steam pipe is intended to be insulated with two layers of insulating materials of different thermal conductivities. For minimum heat transfer to take place_________________?
A. The better insulation material should be put just next to pipe (i.e., inside)
B. The better insulating material should be put outside
C. Either of the insulating material could be put on either side
D. Steam temperature is considered before deciding as to which insulating material is to be put
inside (i.e., just next to the pipe)
