Bissoy
Login
Get Advice on Live Video Call
Earn $ Cash $ with
consultations on Bissoy App
A bed consists of particles of density 2000 kg/m<sup>3</sup>. If the height of the bed is 1.5 metres and its porosity 0.6, the pressure drop required to fluidise the bed by air is
A
25.61 kPa
B
11.77 kPa
C
14.86 kPa
D
21.13 kPa
Correct Answer:
11.77 kPa
A bed of spherical particles (specific gravity 2.5) of uniform size 1500 μm is 0.5 m in diameter and 0.5 m high. In packed bed state, the porosity may be taken as 0.4. Ergun's equation for the above fluid-particle system (in SI units) is given below:
Δ P/L = 375 × 10
3
V
OM
+ 10.94 × 10
6
V
2
OM
(SI units)
If water is to be used as the fluidising medium, in actual operation, the above bed has a height = 1 m. What is the porosity of the fluidised bed?
A
0.2
B
0.5
C
0.7
D
0.8
Bed pressure drop in an air fluidised bed of catalyst particles (ρ
p
= 200 kg/m
3
, D
p
= 0.05 cm) of 60 cm bed depth and bed porosity of 0.5 expressed in cm of water (manometer) is
A
90
B
60
C
45
D
30
The dimensions of a room are 12.5 metres by 9 metres by 7 metres. There are 2 doors and 4 windows in the room; each door measures 2.5 metres by 1.2 metres and each window 1.5 metres by 1 metre. Find the cost of painting the walls at Rs. 3.50 per square metre.
A
Rs. 150.50
B
Rs. 1011.50
C
Rs. 1101.50
D
Cannot be determined
A gas (density = 1.5 kg/m
3
, viscosity = 2 × 10
-5
kg/m.s) flowing through a packed bed (particle size = 0.5 cm, porosity = 0.5) at a superficial velocity of 2 m/s causes a pressure drop of 8400 Pa/m. The pressure drop for another gas, with density of 1.5 kg/m
3
and viscosity of 3 × 10
-5
kg/m.s flowing at 3 m/s will be
A
8400 Pa/m
B
12600 Pa/m
C
18900 Pa/m
D
16800 Pa/m
A woman while shopping in a mall pushes her trolley 20 metres through an alley which is going East, then she turns to her left and walks 30 metres, then she turns West and walks another 30 metres, then she turns South and walks 30 metres and then she turns West and walks 25 metres. Where is she now with reference to her starting position?
A
35 metres West
B
5 metres West
C
35 metres East
D
5 metres East
Rajan walks 24 metres towards east. Then turns right and walk another 24 metres. Then turn right and walks for 31 metres to reach shop A. He again turns to his right and walks for 24 metres. What is the straight line distance (in metres) between the starting point and shop A?
A
14\u221a2
B
15\u221a2
C
25
D
26
What part of a ditch, 48 metres long, 16.5 metres board and 4 metres deep can be filled by the earth got by digging a cylindrical tunnel of diameter 4 metres and length 56 metres ?
A
$$\frac{1}{9}$$
B
$$\frac{2}{9}$$
C
$$\frac{7}{9}$$
D
$$\frac{8}{9}$$
Kritika walks 40 metres towards south. Then turning to her right she rides 30 metres. Then, turning to her left, she rides 50 metres. Again, she turns toher left and rides 30 metres. How far (in metres) is she from her initial position?
A
65
B
70
C
80
D
90
Your network consists of Windows 2000 file servers, Windows 2000 print servers, Windows 2000 professional computers, Windows 2000 file servers. You must prevent any unsigned drivers from being installed on any computer in your Windows 2000 network. What should you do?
A
Configure a Group policy for the Domain that blocks all unsigned drivers
B
Configure a Group policy for the Default Domain Controller to block all unsigned drivers
C
Configure the Windows 2000 file servers, Windows 2000 print servers, Windows 2000 professional computers and Windows 2000 file servers to block unsigned drivers
D
Do nothing, this is the default setting
E
None of above
A 0.5 m high bed made up of a 1 mm dia glass sphere (density 2500 kg/m
3
) is to be fluidised by water (density 1000 kg/m
3
). If at the point of incipient fluidisation, the bed voidage is 40%, the pressure drop across the bed is
A
4.4 KPa
B
2.94 KPa
C
3.7 KPa
D
None of these