Engineering Questions with Answers - Multiple Choice Questions

# Mechanical Operations MCQ’s – Filtration Introduction

1 - Question

As the solids are deposited, the cake resistance will ______
a) Decrease
b) Increase
c) Constant
d) Stable

Explanation: The resistance of filter cake will increase as solids are deposited but the other resistances will remain constant throughout the process.

2 - Question

What does the below equation represents? a) Velocity of cake
b) Velocity of filtrate
c) Velocity of discharge
d) Invalid relation

Explanation: If dP is the pressure difference across a small thickness dl of cake, the velocity of flow of the filtrate, where r is specific resistance of filter cake.

3 - Question

What is an optimum speed of a basket centrifuge?
a) 100 to 500 rpm
b) 800 to 1800 rpm
c) 1500 to 2000 rpm
d) 200 to 500 rpm

Explanation: The speed of the basket is so high 800 to 1800 rpm and the load great often over 1000 pounds, if the basket shaft on fixed bearings.

4 - Question

Centrifuge and automatic discharges are used for ________
a) Crystalline and product removal
b) Amorphous and feed removal
c) Crystalline and feed removal
d) Amorphous and product removal

Explanation: When the centrifuge is used for handling materials as crystalline products, automatic dischargers are used for removing the product.

5 - Question

a) Torque
c) Axial
d) Longitudinal

6 - Question

a) Decrease
b) Increase
c) Constant
d) Stable

7 - Question

In a conical screen filter, the liquid is impelled through a _________
a) Centrifuge
b) Torque
c) Escaper
d) Desolater

Explanation: When a conical screen is rotated about its axis, centrifuge force will impel a liquid through the openings in the screen.

8 - Question

________ the steepest angle at which a sloping surface formed of loose material.
a) Angle of nip
b) Angle of crutch
c) Angle of Dump
d) Angle of repose

Explanation: The angle of repose or critical angle of repose of a granular material is the steepest angle of descent relative to the horizontal plane.

9 - Question

Suppose the particles of a sump are sliding across a cone, which of the following is true?
a) Cos Ө = α
b) Cos Ө/2 < α
c) Ө = α
d) Ө/2 > α

Explanation: If the half angle of cone screen is greater than the angle of repose of the solids, the solids will slide across with velocity of independent feed rate.

10 - Question

If angle of repose is too low, then velocity is _________
a) Constant
b) Low
c) High
d) Optimum