Miscellaneous In Metallurgy - Study Mode

Show All Answers

[#211] During fully developed laminar flow in a circular pipe, the velocity profile is parabolic, and symmetric around the axis. The velocity at the tube wall is zero. The ratio of the average velocity to the maximum velocity is

(A) $$frac{1}{{64}}$$

(B) $$frac{1}{2}$$

(C) $$frac{2}{3}$$

(D) $$frac{3}{4}$$

Correct Answer

(B) $$frac{1}{2}$$

[#212] A furnace wall consists of two layers. The inside layer of 450 mm is made of light weight bricks of thermal conductivity IW/m.K and outside layer of 900 mm is made of refractory of thermal conductivity 2W/m.K. The hot face of the inside layer is at temperature 1300 K and the cold face of the outer layer is at 400 K. The temperature at the interface between the two layers is . . . . . . . . K.

(A) 1000

(B) 850

(C) 700

(D) 600

Correct Answer

(D) 600

[#213] What is the purpose of fiberglass that is made as a thread?

(A) Insulating material

(B) Conductive material

(C) Heat resistant

(D) Cloth

Correct Answer

(D) Cloth

[#214] A particle is settling in a liquid under Stokesian conditions. The free settling velocity of the particle is proportional to

(A) $$sqrt {{ ext{particle diameter}}} $$

(B) particle diameter

(C) (particle diameter) 2

(D) (particle diameter) 3

Correct Answer

(B) particle diameter

[#215] A furnace wall consists of four layers of different materials, M 1 , M 2 , M 3 and M 4 . If the layers are of equal thickness and the steady state temperature profiles is as shown below, then the material with the lowest thermal conductivity is

(A) M 1

(B) M 2

(C) M 3

(D) M 4

Correct Answer

(A) M 1