Science for All July edition

8/14/2019 Science for All July edition

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SCIENCEFORALL

Science made simple

SCIENCE FOR ALL Page 1

JULY 2009


2/22

CONTENT

1. EDITORIAL ------------------------------------------------------------------------------------------03

2. THE GAINTS OF SCIENCE Galileo Galilei ----------------------------------------------04

3. KNOW YOUR SOLAR SYSTEM Mercury------------------------------------------------104. MATHS CORNER Vedic Mathematics--------------------------------------------------12

5. HOW DOES IT WORK? DVD Technology -------------------------------------------------16

6. THE HUMAN BODY Cell ----------------------------------------------------------------------19

SCIENCE IN NEWS Highlights of This Month---------------------------------------------22



3/22

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5/22

he gave up this course and left without

completing his medical degree.

To earn a living, Galileo Galilei started

tutoring students in mathematics. First he

started privately in Florence and then during

1585-86, at Siena, he held a public

appointment. During the summer of 1586 he

taught at Vallombrosa, and in this year he

wrote his first scientific book The little

balance [La Balancitta] which described

Archimedes' method of finding the specific

gravities (that is the relative densities) of

substances using a balance. By this his

journey of unfolding of discoveries and

inventions started. Galileo desperately

wanted to teach mathematics at the

University of Bologna but he failed to

impress Clavius who was professor of

mathematics there. But for ambitious and

brilliant Galileo opportunities were not less.

Very soon Galileo received a prestigious

invitation to lecture on the dimensions and

location of hell in Dante's Inferno at the

Academy in Florence. In 1589 he was

appointed for chair of mathematics at

University of Pisa (same university from

which he never got the degree). When

Galileo arrived at the University, some

debate had started up on one of Aristotle's"laws" of nature that heavier objects fell

faster than lighter objects. Aristotle's word

had been accepted as gospel truth, and

there had been few attempts to test

Aristotle's conclusions by actually

conducting an experiment!

According to legend, Galileo decided to try.

He needed to drop the objects from a great

height. The perfect building was right at

hand, the Tower of Pisa, 54 meters tall.

Galileo climbed up to the top of the building

carrying a variety of balls of varying size

and weight, and dumped them off of the top.

They all landed at the base of the building at

the same time (legend says that the

demonstration was witnessed by a huge

crowd of students and professors). Like this

he proved Aristotle wrong. With the coming

of power in hand Galileo grew arrogant and

rude. It was because of this fact that the

University of Pisa chose not to renew

Galileo's contract.


In year 1590, he wrote De Motu, a series ofessays on the theory of motion which he

never published. It is likely that he never

published this material because he was less

than satisfied with it. Actually that time he

was quite mistaken that the force acting on

a body was the relative difference between

its specific gravity and that of the substance

through which it moved. He returned to workon the theory of motion in 1602 and over the

following two years, through his study of

inclined planes and the pendulum, he

formulated the correct law of falling bodies

and worked out that a projectile follows a


6/22

parabolic path. In 1602-1604, he completed

his work on discourses which reflected his

work on inclination. In this he assumed that

the speed acquired by the same movable

object over different inclinations of the plane

are equal whenever the heights of those

planes are equal.

In 1591, Vincenzo Galilei, Galileo's father,

died and since Galileo was the eldest son

he had to provide financial support for the

rest of the family and, in particular, have the

necessary financial means to providedowries for his two younger sisters. Being a

professor of mathematics at Pisa he was

not well paid. So Galileo looked for a more

lucrative post. Galileo was appointed

professor of mathematics at the University

of Padua (the University of the Republic of

Venice) in 1592 at a salary three times of

what he had received at Pisa. On 7December 1592 he gave his inaugural

lecture and that marked the beginning of a

period of eighteen years at the university.

These were the years that he later

described as the happiest years of his life.

At Padua his duties were mainly to teach

Euclid's geometry and standard (geocentric)

astronomy to medical students, who would

need to know some astronomy in order to

make use of astrology in their medical

practice. After this his real work of making of

telescope started for which he is

remembered the most. Galileo began to

make a series of telescopes whose optical

performance was much better than that of

the Dutch instrument. His first telescope

was made from available lenses and gave a

magnification of about four times. To

improve on this Galileo learned how to grind

and polish his own lenses and by August

1609 he had an instrument with a

magnification of around eight or nine.

Galileo immediately saw the commercial

and military applications of his telescope

(which he called a perspicillum) for ships at

sea. In about two months, December and

January, he made more discoveries that

changed the world than anyone has ever

made before or since, as had turned his

telescope on the night sky and began to

make remarkable discoveries. Galileos

astronomical discoveries are described in a

short book called the Starry Messenger

published in Venice in May 1610.


Galileo never married. However, he had

brief relationship with Marina Gamba, a

woman he met on one of his many trips to

Venice. Marina lived in Galileo's house in

Padua where she bore him three children,

two daughters Virginia and Livia and son

Vincenzio. In 1610, Galileo moved from

Padua to Florence where he took a position

at the Court of the Medici family. He left

Vincenzio, with Marina Gamba in Padua. In

1613, Marina married Giovanni Bartoluzzi,

and Vincenzio joined his father in Florence.
http://www-history.mcs.st-andrews.ac.uk/Mathematicians/Euclid.htmlhttp://www-history.mcs.st-andrews.ac.uk/Mathematicians/Euclid.html


7/22

For Galileo saying that the Earth went

around the sun changed everything since

he was contradicting the techings of the

church, While some of the churchs

mathematicians wrote that his observations

were clearly correct, many members of the

church believed thathe must be wrong.

Galileo Galilei was 68 years old and sick.

Threatened with torture, he publicly

confessed that he had been wrong to have

said that the Earth moves around the Sun.

Legend then has it that after his confession

Galileo quietly whispered but yet, it.

Galileo Galilei was a religious man, and

agreed that the Bible could never be wrong.

However, he said, the interpreters of the

Bible could make mistakes, and it was a

mistake to assume that the Bible had to be

taken literally. This might have been one of

Galileo's major mistakes. At that time, only

Church priests were allowed to interpret the

Bible, or to define God's intentions. So there

were lots of controversies & oppositions on

this and his discovery that earth moves

around sun. In December of 1613, a

powerful member of the nobility said that

she could not see how his observations

could be true, since they would contradict

the Bible. The lady quoted a passage in

Joshua where God causes the Sun to stand

still and lengthen the day. How could this

mean anything other than that the Sun went

around earth?

moves." Galileo died of natural causes in

1642, after having gone blind. It was a sad

end for such a great a man to die

condemned of heresy. He wished to be

buried beside his father in the family tomb in

the Basilica of Santa Croce, but there were

lot of opposition from the Church. He was

reburied at Santa Croce, sacred ground, in

1737. In 1741, Pope Benedict XIV

authorized publication of Galileo's complete

works. Heliocentrism was formally

rescinded as heresy in 1758.

It was not until October 31, 1992, that the

Church under Pope John Paul II expressed

regret over how Galileo had been treated, in

response to a Pontifical Council for Culture

study. Galileo Galilei is one of the most

influential and famous scientists in human

history, having contributed to a wide range

of fields.

Necessity is the Mother of Invention

Galileo Galilei

Scientific achievements:

Kinematics:


At age twenty, Galileo noticed a lamp

swinging. Curious mind of Galileo wanted to

know how long it took the lamp to swing

back and forth; he used his pulse to time

large and small swings. Galileo discovered

something that no one else had ever

realized: the period of each swing was


8/22

exactly the same. He formulated the times-

squared law, which states that the vertical

distance covered by an object in free fall or

along an inclined plane is proportional of the

square of the time of the fall.

S= gt2/2

He also identified the parabola as the ideal

trajectory for uniformly accelerated motion

in plane.

He was the one who proposed a principle of

inertia, which became the foundation of

Newtons First law motion.

Astronomy:

In 1608, the telescope was invented in the

Netherlands. Over the next year, Galileo

gave his own improvements on this

invention. As this scientist trained his

telescope on the objects of sky, he viewed a

surface that was uneven, rough, and full of

cavities and prominences. Later it was

realized that this was the view of the surface

of moon. He continued his work of

improvement of power of his telescope. On

January 7, 1610, he turned his 30 power

telescope towards Jupiter, and found three

small, bright stars near the planet. One was

off to the west, the other two were to the

east, all three in a straight line. Thefollowing evening, Galileo once again took a

look at Jupiter, and found that all three of

the "stars" were now west of the planet, still

in a straight line. Observations over the

following weeks lead Galileo to the

inescapable conclusion that these small

"stars" were actually small satellites that

were rotating about Jupiter. And there were

more discoveries via the new telescope: the

appearance of bumps next to the planet

Saturn (Galileo thought they were

companion stars; the "stars" were actually

the edges of Saturn's rings), spots on the

Sun's surface (though others had actually

seen the spots before), and seeing Venus

change from a full disk to a sliver of light. .

This, along with observing the phases of

Venus, provided support for the Copernican

heliocentric model of the universe over

ptolemys geocentric model.

Galileo Galilei published his findings on

astronomy in a small book titled The starry

Messenger. He wrote Dialogue on the two

Great Systems of the world this book talked

about the Copernican system.

Unfortunately, the book turned out to be

biased in favor of heliocentrism and the

Pope did not appreciate the perceived

public ridicule. Galileo was ordered to stand

trial of suspension of heresy in 1633.

Others:


Galileo came up with rudimentary

thermometer which, for the first time,

allowed temperature variations to be

measured and an ingenious device to raise

water from aquifers found no market.


9/22

In 1596 with an invented military compass

that could be used to accurately aim

cannonballs.



10/22

KNOW YOUR SOLAR SYSTEM

Mercury

The Fastest-Moving Planet

Mercury was first spotted by Italian

astronomer Galileo in 1610. Mercury is the

nearest to sun and fastest moving Planet

in the Solar System. Until 1960s

astronomers believed that Mercury rotated

once every 88 Earth days, and took the

same time to go around the sun. But if

Mercury did this, one side of the planet

would always face the sun and the other

side would always be dark. However, radar

studies conducted in 1965 showed that the

planet rotates once in about 59 (58.646)

Earth-days a rotation but it moves around

the sun faster than any other planet about

48 km per second (30 miles). Some people

call mercury The messenger of Gods as

it guards all secrets.

Mercury has an Elliptical Orbit (Oval

shaped). At perihelion (Its closest point) it is

about 46 million kilometer and from aphelion

(its farthest point) it is 70 million kilometer

from the sun. Mercury is about 77.3 million

km (48 million miles) from Earth at itsclosest approach. Mercury is not easily

seen from Earth due to its small angular

separation of 27 from the Sun (less than

the angle made by the hand of the clock at

1 o clock). If one could stand on the

scorching surface of Mercury when it is at

its closest approach, the Sun would appear

almost three times as large as it does when

viewed from Earth.

As mercury is very close to Sun, one can

observe this planet from the ground-based

telescope of earth only during the day when

scattered sunlight impedes clear views ofthe planet, or just before sunrise and after

sunset, when the light must pass through it

10 times as much as atmospheric

turbulence as when it is overhead.

Unfortunately the best earth based

telescope get a worse view of it than

humans get of the moon with naked eye

each night.

Mercury possesses a thin exosphere made

up of atoms blasted off its surface by the

solar wind and striking Meteoroids rather

than a atmosphere. Because of the planet's


Mass: 3.30e23 kg (5.5% of Earth's)

Diameter: 4,878km (3,032 miles) at its equator

Temperature: 350 C during the day and 170 Cduring night

Average Distance: About 58 million km (36 millionmiles)

Period of Rotation: 58.6462 days.


11/22

extreme surface temperature, the atoms

quickly escape into space. With the thin

exosphere, there has been no wind erosion

of the surface and meteorites do not burn

up due to friction as they do in other

planetary atmospheres. Mercury's surface

resembles that of Earth's Moon, scarred by

many impact craters resulting from

collisions with meteoroids and comets.

While there are areas of smooth terrain,

there are also lobe-shaped scarps or cliffs,

some hundreds of miles long and soaring

up to a mile high, formed by early

contraction of the crust. The Caloris Basin,

one of the largest features on Mercury, is

about 1,300 kilometers (800 miles) in

diameter. It was the result of an asteroid

impact on the planet's surface in the early

history of our solar system. Over the next

half-billion years, Mercury shrank in radius

about 1 to 2 kilometers (0.6 to 1.2 miles) as

the planet cooled after its formation. In

1991, astronomers using radar observations

showed that Mercury may have water ice at

its north and south poles inside deep craters

that are perpetually cold (below -212

degrees Celsius or -350 degrees

Fahrenheit). Falling comets or meteorites

might have brought ice to these regions ofMercury, or water vapor might have out

gassed from the interior and frozen out at

the poles.

Broadly Planet Mercury is made up of 3

layers1) Core

2) Rocky mantle

3) Fine Soil

Mercury has a big iron Core which makes

about 75% of whole planets diameter and

above the core is rocky mantle and crust

about 600 km thick. The surface is cratered

and like the moon it is covered in finesoil.Mercury's rolling, dust-covered hills have

been eroded from the constant

bombardment of meteorites.

Mercury is the only planet other than earth

which has magnetic field on it but because

of its closeness to the Sun, it does not have

atmospheric conditions to sustain life. Since

Pluto was reclassified as a dwarf planet in2006, Mercury is now the smallest planet in

our solar system.



12/22

MATHS CORNER

Vedic Mathematics

Nikhilam Navastascaramam Dasatah

In the last edition we discussed about the

evolution of Vedic mathematics and how

vedic mathematics simplifies our

mathematical calculations. We have learnt

Ekadhaikena Purvena sutra which made

squaring of the numbers ending with 5 a lot

simpler and time saving. In this edition well

discuss second sutra known as NikhilamNavastascaramam Dasatah. Nikhilam

Navastascaramam Dasatah means all

from 9 and the last from 10. By using this

sutra, multiplication of two numbers which

are near to bases 10, 100, 1000etc can

be simplified.

Now lets take an example to understand

how we can use Nikhilam

Navastascaramam Dasatah sutra in

multiplying and Division.

Nikhilam Multiplication:

It would be easy to understand nikhilam

multiplication by taking an example

Suppose we want to multiply 7 and 8

Step 1-

Here base is 10, since both the numbers

are near 10

Step 2-

Take the deviation of both the number from

10, by this we get two remainders one 3

(10-7) and other 2 (10-8).

Step3-

R.H.S of the answer is given by 2 * 3 = 6

The R.H.S. of the answer is the product ofthe deviations of the numbers. It shall

contain the number of digits equal to

number of zeroes in the base. If R.H.S.

contains less number of digits than the

number of zeros in the base, the remaining

digits are filled up by giving zero or zeroes

on the left side of the R.H.S. If the numbers

of digits are more than the number of

zeroes in the base, the excess digit or digits

are to be added to L.H.S of the answer

since base is 10, so

Step 4

LHS of the answer is 5

To find L.H.S of the answer, we can use any

one of the four ways depending on the

numbers

1) Subtract deviation 2 from the First

Number 7 i.e., (7-2) = 5.


2) Subtract deviation 3 on the first row

from the second number i.e., (8 3)

= 5


13/22

3) Subtract the base 10 from the sum

of the given numbers i.e., (7 + 8)

10 = 5

4) Subtract the sum of the two

deviations from the base i.e., 10 (3

+ 2) = 5

This gives 7 * 8 = 56

Lets take another example of two digit

number

Eg = 97 * 93

Step 1 -

Here base is 100 so two deviations are 3

(100-97) and 7 (100-93),

Step 2 -

By multiplying the deviations we will get

R.H.S - 3 * 7 =21

Step 3 -

To get L.H.S of the answer (we can use 1 or

2 method) 97-7 =90

Answer is 97 * 93 = 9021

Lets take another example of three digit

number:

Say, 750 * 995

Step 1-

Here base is 1000 so deviations are 250

(1000-750) and 5 (1000-995)

Step 2-

For R.H.S multiplying the two deviations

250 * 5 =1250

Step 3-

For L.H.S 750 5 =745(If the numbers of

digits are more than the number of zeroes in

the base, the excess digit or digits are to be

added to L.H.S of the answer since base is

10)

Therefore Answer is 746250

Nikhilam Division:

By nikhilam process of division, even

lengthier divisions do not involve no division

or no subtraction but only a few

multiplications of single digits with small

numbers and a simple addition. But nikhilam

division is applicable to only few cases.

Consider some two digit numbers

(dividends) and divisor 9

Say, 13 divided by 9

According to traditional method division will

be carried as follows

9) 13 (1

9

4



14/22

Now By Nikhiliam Division, division will be

reduced merely in to multiplication and

addition

Step 1

Split each dividend into a left hand part for

Quotient and right hand part for remainder

by a slash

13 as 1 / 3

Step 2

Put the first digit of the dividend as left hand

part of the answer and the add same digit to

right hand part for the remainder

9) 1 / 3

1

1 / 4

By this answer is Q = 1, R = 4

Similar operation can be performed on

Eg = 43 / 9

9) 4 / 3

4

4 / 7

Q = 4, R = 7Now lets take examples of 3 & 4 digitnumbers

Eg = 106 / 9

9) 10 / 6

1 / 1

11 / 7

Q = 11, R = 7

Eg = 404 / 9

9) 40 / 4

4 / 4

44 / 8

Q = 44, R = 8

Eg = 1206 /9

9) 120 / 6

13 / 3

133 / 9

Simpler steps can be carried with more

than 4 digit number

In all the cases mentioned above, the

remainder is less than the divisor. Now

lets take few cases when remainder is

equal or greater than divisor

Eg = 36 / 9

9) 3 / 6 9) 24 / 6

3 2 / 6

3 / 9 26 / 12

(R is equal to divisor) (R is greater than divisor



15/22

In such cases we proceed by re dividing the

remainder by 9 and carrying over this

quotient at quotient side

Now apply Nikhilam Navastascaramam

Dasatah to calculate multiplication and

division some other numbers and soon

youll master this technique9) 3 / 6 9) 24 / 6

/ 3 2 / 6

3 / 9 26 / 12

4 / 0 (After splitting)

26 / 1 / 2

/ 1

1 / 3

27 / 3

Q= 27, R = 3



16/22

HOW DOES THIS THING WORK?

DVD Technology

A Mark of clarityAs of the beginning of the twenty-first

century and with the advancement of

technology, Data, Audio & Video storage

medium has also turned from Magnetic

Tapes (Video Cassette) to DVDs. DVD

stands for Digital Versatile Disk or

Digital Video Disk. DVDs are Optical

high-density storage media for storing data,Audio & videos. This technology is

successor to Compact Disk popularly known

as CDs and replaced VHS tapes and Laser

Disk in entertainment industry. DVDs store

data by digital technology. A DVD of same

dimension as a CD can store five to ten

times as much data as one can store in CD.

It can store up to 17 Giga bytes of data. A

DVD provides much sharper images than a

VHS (Video Home System) videotape due

to the use of MPEG-2 compression (MPEG

stands for Moving Pictures Experts Group)

and Compression refers to the process of

condensing various audio and video signals

into less space while improving the quality.

In its most basic form, a DVD is one 0.02-

inch-thick (0.06-centimeter-thick) disc; at its

greatest capacity, a DVD is two such discs,

compressed together to create a double-

sided disc 0.04 inch (0.12 centimeter) thick.

It is circular wafer of plastic and metal

usually Aluminum, with a diameter of 4.75

inches (12 centimeter) and a hole in the

center. Data is converted in digital form

(Binary language ones and zeros) and this

digital data used in DVDs is encoded onto a

master disc. This disc is then used to create

copies of it. Each writable layer of a DVD

has a spiral track of data, track alwayscircles from the inside of the disc to the

outside. A laser (a device used to create a

narrow, intense beam of very bright light) is

use to burn small holes, called pits, into a

microscopic layer of metal. These pits

correspond to the binary ones and smooth

areas of the disc untouched by the laser,

called land, correspond to the binary

zeroes. Once the pits have been burnt, the

metal is coated with a protective,

transparent layer so that data will not get

destroyed. There are Dual layer DVDs also

available. Dual layer DVD can store upto

8.54 gigabytes per disk as compared with

4.7 gigabytes per single layer of disk. A

dual-layer disc differs from its usual DVD

counterpart by employing a second physical

layer within the disc itself.


Now to read a DVD we require a DVD

player.


17/22

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18/22


DVD and convert it to six separate analog

channels. This feature is not necessary if

you have a Dolby Digital receiver, which has

a digital input that carries all of the audio

information.

- DTS (Digital Theater Systems)

All DVD players are DTS compatible. They

pass the digital audio information on to the

receiver, which then decodes it.

96 kHz/24-bit DAC

This is the speed and accuracy of the

digital-to-analog converter (DAC), which

converts the audio information into an

analog signal. Most movie soundtracks are

encoded in this format, so this is really a

required feature, and most DVD players

should have at least a 96 kHz/24-bit DAC.

Simulated surround

If you are going to hook the DVD player up

to a TV or a stereo system with only two

speakers, a DVD player with simulated

surround processing will give you some

sense of surround sound without the extra

speakers.

Audio Decoders

Some DVD players should have built-in

Dolby Digital and DTS decoders; others rely

on the receiver to decode the audio tracks

on a disc.

Six-Channel analog outputs

These analog outputs are used for playing

multichannel Blu-ray, HD-DVD, SACD and

DVD-Audio discs if the player has a built-in

decoder for these formats. Six channel

analog outputs connect to corresponding

analog inputs on a receiver.

Picture enhancement

Progressive Scan, Video sampling

Number of DVDs DVD player can

change


19/22

SCIENC

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20/22

SCIENC

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21/22


As plant prepare its own food, Plant cell

have one more component called

chloroplast

Chloroplast: The chloroplast allows plantsto harvest energy from sunlight.

Specialized pigments in the chloroplast

(including the common green pigment

chlorophyll) absorb sunlight and use this

energy to make food for plant.

Cells undergo a cell cycle, or cell-division

cycle, it is a series of events that take place

in a cell leading to its division and

duplication.

In cells without a nucleus (prokaryotes), the

cell cycle occurs by a process known as

binary fission. In cells with a nucleus

(eukaryotes), the cell cycle can be divided in

two brief periods: inter-phase during which

the cell grows, accumulating nutrients

needed for mitosis and duplicating its DNA

and the mitosis-phase, during which the cell

splits itself into two distinct cells, often

called "daughter cells". The cell-division

cycle is a vital process by which a single-

celled fertilized egg develops into a mature

organism, as well as the process by which

blood cells, hair, nail and some internal

organs are renewed.


22/22

SCIENCE NEWS

Some Highlights of This Month

New Fluorescent Silicon

Nanoparticle Discovered

New Researchers in the Department of

Physics and Astronomy at the University

of Leicester have developed a new

synthesis method, which has led them

to the discovery of fluorescent silicon

nanoparticles and may ultimately help

track the uptake of drugs by the body'scells.

Breakthrough in development of tiny

Biological fuel cell

University of Georgia researchers have

developed a successful way to grow

molecular wire brushes that conduct

electrical charges, a first step indeveloping biological fuel cells that

could power pacemakers, cochlear

implants and prosthetic limbs.

New test can detect both genetic and

chromosomal abnormalities in

Embryos

The researchers based in the USA andthe UK have been able to prove that the

technique, known as genome-wide

karyomapping, is capable of not only

detecting diseases caused by a specific

gene mutation, in this case cystic

fibrosis, but that it would also capable of

detecting aneuploidy (an abnormal

number of any of the 23 pairs of

chromosome) at the same time. This is

the first time they have been able to

demonstrate that the test can work in

cells taken from embryos that have

already been diagnosed with the cystic

fibrosis gene mutation using

conventional pre implantation genetic

diagnosis (PGD).

After 18 years mission the solar

probe Ulysses retires

The solar probe Ulysses has circled the

sun for more than 18 yearsalmost as

long as the Greek hero Odysseus, also

called Ulysses, Ulysses will receive its

final transmission, as researchers say

the scientific findings sent home by the

failing spacecraft no longer justify the

missions costs. After shut- off, Ulysses

will continue to orbit the sun, becoming

in effect man- made Comet.


Science for All July edition

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