Mechanical Operations Quiz 2

1 / 50

**Dust collection efficiency of electrostatic precipitator can be as high as 99.9%. Maximum temperature and pressure of dust laden gas that can be cleaned in an electrostatic precipitator is respectively ?**

2 / 50

**Cyclones are used primarily for separating__________?**

3 / 50

**Dry powdery solid materials are transported by a _______ conveyor?**

4 / 50

**Bond crushing law__________?**

5 / 50

**Cake resistance is_____?**

6 / 50

**Ball mill is used for___________?**

7 / 50

**During agitation of liquids, power consumption during laminar flow is not proportional to the _________?**

8 / 50

**Close circuit grinding by a ball mill with air sweeping employs a _________?**

9 / 50

**Crushing efficiency of a machine ranges between ___________ percent?**

10 / 50

**Balls for ball mills are never made of__________?**

11 / 50

**Capacity of flight conveyor in tons/hr is given by (where, W & D = width and depth of flight respectively in metre V = speed of the conveyor, metre/second ? = bulk density of material, kg/m3) ?**

12 / 50

**Dust laden air can be purified using a______?**

13 / 50

**Diatomaceous earth is a/an__________?**

14 / 50

**During agitation of liquids, the__________?**

15 / 50

**Energy requirement (per unit mass of material crushed/ground) is highest for___________?**

16 / 50

**Cement clinker is reduced to fine size by a _______?**

17 / 50

**Capacity (in tons/hr) of jaw/gyratory crusher is equal to (where, L = length of the receiving opening, cm S = greater width of the discharge opening, cm) ?**

18 / 50

**Chance process is used for the_________?**

19 / 50

**As per Taggart?s formula, the capacity (kg/hr) of Jaw & Gyratory crushers (for gapes of 10 to 60 cms) is equal to (where, L = Length of feed opening, cms S = Maximum width of discharge opening, cms) ?**

20 / 50

**Apron conveyors are used for _____ ?**

21 / 50

**At low Reynold?s number, the power (P) required for agitating a fluid in a stirred tank becomes independent of inertial forces. In this limit, indicate which of the following relations is satisfied: Po = ?/?N3 D5: Power number Re = ? N D2/?: Reynold?s number N is the impeller rotational speed, and D is the impeller diameter ?**

22 / 50

**Choke crushing (in case of a Jaw crusher) compared to free crushing___________?**

23 / 50

**Colloid mills achieve size reduction mainly by_____?**

24 / 50

**During washing of filter at the end of constant pressure filtration, the rate of washing equals the rate of filtration_____?**

25 / 50

**Feed size of ? 25 cms can be accepted by _________?**

26 / 50

**All resistances during washing of cake _______?**

27 / 50

**As the product becomes finer, the energy required for grinding_____?**

28 / 50

**Arrange the following size reduction equipment in the decreasing order of the average particle size produced by each of them ?**

29 / 50

**Ball mills and tube mills with flint or porcelain balls are used for size reduction of________?**

30 / 50

**Bucket elevators are not suitable for the vertical lifting of __________ materials?**

31 / 50

**Equivalent diameter of a particle is the diameter of the sphere having the same ___________?**

32 / 50

**Critical speed of rotation, N (in rps ? rotation per second) of a trammel is equal to (where, g = acceleration due to gravity = 9.81 m/sec2 and, r = radius of trammel, metre.) ?**

33 / 50

**Coal is finally pulverised to 200 mesh size for burning in boilers by a_____?**

34 / 50

**Crushing efficiency is the ratio of the ________ ?**

35 / 50

**During filtration operation, the filtrate encounters the resistance of the _____?**

36 / 50

**Compressibility co-efficient for an absolutely compressible cake is________?**

37 / 50

**Angle of nip of the crushing rolls does not depend upon the________?**

38 / 50

**Dispersion of a gas through liquid is done by using a___________?**

39 / 50

**During the washing of cake__________?**

40 / 50

**As particle size is reduced___________?**

41 / 50

**Colloidal mills are used for _______ grinding?**

42 / 50

**Cartridge filters are termed as ?edge? filters, because of the fact that the__________?**

43 / 50

**Crushing of mineral particles is accomplished in a ?cage mill?, when one or more alloy steel bars are revolved in opposite directions. It is a type of _______ mill?**

44 / 50

**Energy consumption in a crusher decreases with increase in the__________?**

45 / 50

**During size reduction by a jaw crusher, the energy consumed decreases with the___________?**

46 / 50

**Basic slag is not ground in__________?**

47 / 50

**Critical Speed (Nc) of a ball mill is given by (where R1 and R2 are radii of ball mill and the ball respectively) ?**

48 / 50

**Carbon black is pulverised in a________?**

49 / 50

**Cumulative analysis for determining surface is more precise than differential analysis, because of the________?**

50 / 50

**Energy consumed for crushing one ton of material ranges from _______ kWh?**

Provide Your Information