Q. & A.s ‑‑‑ SCI.
& TECH. – 17
451Q. Why there is numbness
in the limbs?
1.
Poor
blood supply
2.
Cholesterol
3.
Abnormal
Ca, K, Na
4.
Deficiency
of Vit. B 12
5.
Diabetes
6.
Hypothyroidism
452Q. why do we get sleep after lunch?
When
we eat food, the stomach is filled with food which is to be churned so that it can be digested after
wards. There are three types of muscle movements in the stomach walls. For the
movement of these muscles blood is needed. So blood comes to stomach. There is a less amount of
blood in the brain. So we get sleep.
453Q. How do municipalities in cold countries supply water in pipes
to houses?
In
cold countries supplying water to houses is very difficult.
Water
freezes at 0o C. The water present in the pipe becomes ice. To avoid
this alcohol is added to water before
supplying. Due to added impurity the freezing point of water goes to “---”
value. So water cannot be frozen.
454Q. why there is ice on the Himalayas?
As
we go up in troposphere, for every 1 km ascent 6.4o C temperature is
reduced. After 6 kms it will below zero. That is why ice is formed on the
Himalayas.
455Q. What is electronic warfare?
If
enemy’s communication is disturbed by jamming on the enemy’s communicating frequency,
the enemy can not send his message to his friend. Because of communication
failure we can win the war. It is called electronic warfare.
456Q. How many types of water are there?
H
hydrogen has 1, 2, 3, 4, 5, isotopes
O oxygen has 14 to 20 isotopes.
H2O, D2O, T2O, HDO,
DTO, etc. there are nearly 100
types of water are there.
457Q. Why doesn’t the shadow of a plane fall on the ground?
It
is due interference of light. One ray falling on the plane and forming a shadow is cancelled by another ray.
Thus the shadows cancel each other because of interference.
458Q. why can’t we make hot pakodies in boiling oil not in boiling
water?
Pakodi
cannot be made in boiling water because both contain water and their boiling
point is same. So the content of water of pakodi cannot be displaced by boiling
water. The temperature of edible oil has nearly 250 degrees or more. So water
from pakodi can be removed immediately.
459Q. Is it necessary to get a Trademark?
Today’s world has cut throat competition
in business. Companies are constantly competing
with one another to gain market share at the expense of the other. Differentiation from other players is only
possible by getting exclusive rights over your name and logo.
460Q. What is SEZ?
SEZ stands for Special Economic Zone. It
is similar to that of China. It was introduced in India in 2000 AD.
This is created as per the regulations
of SEZ Act 2005.
If a firm joins this group
1. Exemption
from custo0ms/excise duties
2. Income tax exemption
3. Exemption
from MAT
4. Exemption from DDT [Dividend Distribution Tax]
5. Exemption
from Service Tax.
461Q. What are the uses of Super conductor?
1. Magnetic-levitation
is an application where superconductors perform extremely well. Transport
vehicles such as trains can be made to "float" on strong
superconducting magnets, virtually eliminating friction between the train and
its tracks.
2. An area
where superconductors can perform a life-saving function is in the field of
biomagnetism.
3. High-energy
particle research hinges on being able to accelerate sub-atomic particles to
nearly the speed of light.
5. Electric
generators made with superconducting wire are far more efficient than conventional
generators wound with copper wire.
6. Other
commercial power projects in the works that employ superconductor technology
include energy storage to enhance power stability.
7. Recently,
power utilities have also begun to use superconductor-based transformers and
"fault limiters".
8. An
idealized application for superconductors is to employ them in the transmission
of commercial power to cities.
9. A petaflop
is a thousand-trillion floating point operations per second. Today's fastest
computers have reached "petaflop" speeds - quadrillions of operations
per second.
10. In the
electronics industry, ultra-high-performance filters are now being built. Since
superconducting wire has near zero resistance, even at high frequencies, many
more filter stages can be employed to achieve a desired frequency response.
11. Superconductors
have also found widespread applications in the military.
13. The
military is also looking at using superconductive tape as a means of reducing
the length of very low frequency antennas employed on submarines.
14. Applications
engineers suggest that superconducting carbon nanotubes might be an ideal
nano-antenna for high-gigahertz and terahertz frequencies, once a method of
achieving zero "on tube" contact
resistance is
perfected.
15. Among
emerging technologies are a stabilizing momentum wheel (gyroscope) for earth-orbiting
satellites that employs the "flux-pinning"
properties of imperfect superconductors to reduce friction to near zero.
16. Superconducting x-ray detectors and
ultra-fast, superconducting light detectors are being
developed due to their inherent ability to detect extremely weak amounts of
energy.
18. Low-temperature
superconductors are expected to continue to play a dominant role in
well-established fields such as MRI and scientific research, with
high-temperature superconductors enabling the newer industries.
19. All of
this is, of course, contingent upon a linear growth rate. Should new superconductors
with higher transition temperatures be discovered, growth and development in
this exciting field could explode virtually overnight.
20. High-temperature
superconductors were used in power plants.
21. The future
melding of superconductors into our daily lives will also depend to a great
degree on advancements in the field of cryogenic cooling.
22. Type 1
superconductors - characterized as the "soft" superconductors - were
discovered first and require the coldest temperatures to become
superconductive.
23. Surprisingly,
copper, silver and gold, three of the best metallic conductors, do not
rank among the superconductive elements. Why is this ?
24. The
periodic table below for all known elemental superconductors (including Niobium,
Technetium and Vanadium which are technically Type 2).
25. Superconductors,
materials that have no resistance to the flow of electricity, are one of the
last great frontiers of scientific discovery.
26. The most
ignominious military use of superconductors may come with the deployment of
"E-bombs".
462Q. What are the elementary properties of Super conductor?
Most
of the physical properties of superconductors vary from material to material,
such as
2. the critical temperature,
3. critical field, and
4. critical current density at which
superconductivity is destroyed.
On
the other hand, there is a class of properties that are independent of the
underlying material. For instance,
all
superconductors have exactly zero resistivity to low applied currents
when there is no magnetic field present or
if
the applied field does not exceed a critical value.
The
existence of these "universal" properties implies that
superconductivity is a thermodynamic phase, and thus possesses certain distinguishing properties which
are largely independent of microscopic details.
462Q. What are the unsolved problems of magnetism?
1.
Earth’s
North changes to South!
2.
Ferromagnetic
iron is sometimes found to be unmagnetised!
463Q. What are Type I Super Conductors?
1.
These
are soft super conductors.
2.
These
are perfect diamagnetisms.
3.
Eg.,
Al, Zn, Hg, Sn, Pb
4.
10-6
metre range is called coherence range.
5.
Super
conductor cannot be penetrated by magnetic flux.
6.
The
origin of their super conductivity is explained by BCS theory.
7.
These
have regularly structured lattice.
8.
The
electrons are coupled over larger distances.
9.
Bond
energy is very low.
10. Little force is
enough to breaking the bond.
11. The ripples through
lattice are called phonons.
12. Phonon is a weak
link.
464Q. What are Type II super conductors?
1.
These
are p-ure super conducting state.
2.
The
magnetic flux lines are rejected.
3.
These
are hard super conductors.
4.
They
carry high current densities.
5.
They
transit from super conducting to the normal state within an increasing magnetic field.
6.
They
super conduct at higher temp.s
465Q. Why while erecting electrical wires, the wires are left
loosely connected?
If
they are tightly connected due to winter cooling, the wires contract and pull
the poles towards the centre of the poles.
466Q. What is the difference between “NET” and “WEB”?
|
Net
|
Web
|
|
Internet
is a network of networks.
On
the Net you find computers.
On
the net the connections are cables between computers.
---
--
---
|
-----
The
Web is an abstract [imaginary] space of information.
On
the Web connections are hyper text links.
The
Web exists because of programs which communicate between computers on the
Net.
The
Web could not be without the Net.
The
Web made the Net useful because people are really interested in information.
|
467Q. When a satellite is launched into geostationary orbit, won’t
there be collision with other satellites?
The
satellite launched into geostationary orbit is placed at 36,000 kms height. In
that orbit it remains where ever it is placed moving at a speed as assigned as
per that height so that the satellite can remain at that place only. That is
why there is no collision.
468Q. What are the types of
orbits for satellites?
1.
Galactocentric
orbit
2.
Helio
centric orbit
3.
Geo
centric orbit
4.
Areo
centric orbit
5.
Geo
synchronous orbit
469Q. What are the different types of Geo synchronous orbit?
1.
Circular
orbit
2.
Elliptical
orbit
3.
Hyperbolic
orbit
4.
Parabolic
orbit
5.
Escape
orbit
6.
Capture
orbit
7.
Graveyard
orbit
8.
Areo
synchronous orbit
9.
Areo
stationary orbit
10. Helio synchronic
orbit
470Q. what are the uses of satellites?
1.
Remote
sensing
2.
Weather
forecasting
3.
Pollution
4.
Internet
5.
DTH
6.
Tele-medicine
7.
Tele-education
8.
Multimedia
9.
Interactive
video
471Q. What are the different regions of satellites?
Region
I Europe, Africa, USSR, Mangolia
Region
II NA, SA, Greenland
Region
III Asia, Australia, SW pacific
472Q. What is Josephson Effect?
It
is the phenomenon of current flow across two weakly coupled superconductors separated
by a very thin insulation barrier. It is
called Josephson Effect.
It
is called Josephson’s Junction.
The
current is called Josephson current.
473Q. What is called Green Computing?
1.
Product
longevity
2.
Algorithmic
efficiency
3.
Resource
allocation
4.
Virtualization
5.
Terminal
servers
6.
Power
management
7.
Materials
recycling
8.
Telecommuting
9.
Newer
hardware
474Q. What is Energy
Efficient Computing?
It
is the practice of using computing devices.
1.
Turn
off your computer when not in use.
2.
If
you don’t for a while, keep in standby mode
3.
Don’t
run computers continuously unless they are in use continuously.
4.
For
small works don’t switch on and off.
5.
Don’t
switch off a computer directly from main switch board.
6.
If it is a laser printer, don’t turn it on
until you are ready to print.
475Q. What does a Software Engineer have?
1.
Technical
2.
Program
Management
3.
Domain
Consulting
4.
Problem
solving
5.
Product
development
6.
Testing
7.
Project
Management
8.
Customer
interface
