Friday, December 28, 2012

Why is it easy to swim in sea than in a river?

                                Why is it easy to swim in sea than in a river?

We know sea water is salty. But river water is fresh water.. It is believed that river water is not salty . Sea water eventhough it has river water , when the river flows long distance to reach sea, the water becomes rich in dissolved salts.
Because of these soluble salts , sea water is having more density than river water. The salt is responsible for the increased density. This density increases the upthrust which helps the body to float in the sea water. Our body sinks less in sea water than in a river.
Hence we find it easy to swim in sea than in a river.

Thursday, December 27, 2012

Mouse of mountains

                                             Mouse of mountains

This name was given to Shivaji from his enemies.
Shivaji was the king of Marathas. He was against Mughals who were in hold of northern India. The story of Aurangajeb , a mughal king and Shivaji is well known.
Shivaji was following guerrilla techniques when he had to fight. As he was ruling a kingdom which had abundant forests and mountains , Shivaji was very expert in using guerrilla techniques .
He was surrounding the enemies in an unexpected manner . When the enemies were ready to start fight, Shivaji and his army were vanished in a fraction of second !
Shivaji had youths from the tribe Malavas , who are well known of forests and also could fight in an unexpected way. Thus, he was called by his enemies by the name mouse of mountains .

Tuesday, December 25, 2012

How is diamond formed?

                                                 How is diamond formed?

In mineralogy , diamond is an allotrope of carbon. , where the carbon atoms are arranged in a variation of face centered cubic crystal . Diamond has the highest hardness and high thermal conductivity. It can be contaminated by very few impurities.
Diamonds are formed at high temperature and pressure in the earth's mantle. Diamonds are brought close to the Earth's surface through volcanic eruptions by a magma which cools into igneous rocks. The formation of diamond requires very specific conditions -------- exposure of carbon bearing materials to high pressures . Diamond is the hardest known natural material on earth.

Monday, December 24, 2012

Infrared rays

                                              Infrared rays

The less dangerous wavelength from Sun's energy is infrared rays. These are the waves that produce heat and are known as thermal waves.
The heat we feel from sunlight, a fire  are all infrared. The infrared wavelength is further broken down into 3 categories -----
1. Near infrared
2. Mid infrared
3. Far infrared
Near infrared are the wavelengths that are used to send messages to TV from remote controls. They are not hot at all , infact we can not feel them too.
Mid infrared are the waves where they begin to produce heat. To these rays, our body's nerve endings can sense. These have the frequency greater than near infra red.
Far infra red rays produce heat. We can find room heaters in cold weather countries during winter. People have far infra red heaters in their houses over there. They only raise the temperature of the object they have been focused on and does not raise the temperature of surrounding free air.

Friday, December 21, 2012

What is ultrasonic sound?

                                      What is ultrasonic sound?

Sound is created through vibrations.  The number of times that a vibration occurs per second is directly related to whether we can hear the sound or not . Any sound that is created by less than 20 vibrations per second , are far too much low in pitch to be detected by human ear.
These kind of sound are said to be in sub-audible range. At the other end of spectrum , lies the sound that vibrate upwards of 20,000 times per second.
These sounds are known as ultrasonic sound  and they are produced at a pitch too high for the human ear to detect. it is well known that bats and even elephants can communicate using these sounds.

Thursday, December 20, 2012

Why do we eat food?

                                                 Why do we eat food?

The question may sound funny. Everyone tell the answer as "to live". But scientifically speaking, the answer is not just that.
Our body is made of tiny and numerous cells. The work of cells is to produce energy. This energy is very essential for our daily activities.
How do cells produce energy? They require  glucose and oxygen for that purpose. Oxygen we will get from breathing. But what about glucose? The food we consume, will finally get reduced to glucose.
Patients are always advised to take glucose as an instant way to produce energy. It would be the instant way. But what we consume food is also get reduced to glucose. That's why we eat food.

Wednesday, December 19, 2012

Ascorbic acid or vitamin C

                                              Ascorbic acid or vitamin C

Vitamin C is also having the name ascorbic acid. It is an essential nutrient for human and other animal species.  Vitamin C is a co factor in atleast 8 enzymatic reactions.
When dis functional it can cause the most severe symptoms of disease scurvy.  In animals, ascorbic acid is most important in wound healing and preventing bleeding from capillaries. Ascorbic acid is a weak sugar acid structurally related to glucose.
The molecules of acid have vitamin C activity ; therefore and are used synonimously with vitamin C , unless otherwise specified.  The deficiency of Vitamin C leads to disease Scurvy . Without this vitamin , the synthesised collagen is too unstable to perform its function.
Scurvy leads to the formation of brown spots on the skin , spongy gums and bleeding from all the membranes.  the person with ailment looks pale , depressed and is partially immobilized. Vitamin C is found in higher concentrations in immune cells.
But it is not certain that how vitamin C interacts with immune cells. 

Tuesday, December 18, 2012

Phenol

                                         Phenol

Phenol , we use it in our house . Phenol is also known as Carbolic acid or Phenic acid.  It is an organic compound with chemical formula C6H5OH.  It is white crystalline at room temperatures.  It is slightly acidic , but requires careful handling since it can cause burns.
Phenol is appreciably soluble in water. It is considered as weak acid.  It can turn blue litmus to slightly to red.    It finds wide clinical uses , Phenol's derivatives are used in preparation of cosmetics  including sunscreens and hair dyes.
It can be used as analgesic.
We use many acids in our house , but they are weak. But concentrated ones are hazardous. 

Monday, December 17, 2012

How does a snake hunt its prey?

                                 How does a snake hunt its prey?

Snakes, while catching its prey uses a combination of senses , relying mainly on smell .
Snake though it has tongue, it dont have any taste buds. A snake's tongue can not sting or prink . Unlike lizards , the tongue is not used in swallowing the prey.
There is a notch on the upper lip of snakes , so the tongue can flick in and out while the mouth remaines closed. Since the tongue is forked , snakes can find and attract mates.
Heat ( infrared rays ) is another important sense , especially for night hunting snakes . The twinned sensors allow snakes to judge distance and also will give the image of the prey in the dark.
Heat sensing is an unique quality of night hunting snakes. They use infrared rays (IR Rays).

Saturday, December 15, 2012

Why do we burp when we drink cold drinks like cola?

                                  Why do we burp when we drink cold drinks like cola?

A burp - sometimes also called belch - is nothing but gas.  When we drink or eat , we dont just swallow liquid or food. We also swallow air at the same time.
Sometimes when we swallow gases like oxygen or nitrogen , they need to get out of the body. That's where burping comes in . Extra gas is forced out of the stomach , out of the mouth as a burp.
After drinking soda or other carbonated beverages , we burp more. The gas that makes these drinks fizzy is carbon di oxide ( CO2 ). It can bring big burps. Sometimes eating or drinking in a hurry , can make a person burp since this can send extra air into the stomach.
Extra air in = more burps out .

Friday, December 14, 2012

What is great red spot?

                                         What is great red spot?

The planet Jupiter is known as great red spot.  The atmosphere of Jupiter is mainly made of molecular hydrogen and helium.
The atmosphere of Jupiter lacks a clear lower boundary. It shows a wide range of active phenomena,  including cyclones, storms and lightning.
The atmosphere consists of great red spot. It is the largest known vortex in the solar system. It could engulf several earths.
Jupiter also has powerful storms, accompanied by lightning strikes. But it is not known exactly what causes great red spot's red colour. But experiments suggest that red colour may be caused by complex organic molecules.

Thursday, December 13, 2012

Liver in human body

                                          Liver in human body

The liver is a vital organ present in vertebrates and in some other animals. it has a wide range of functions including detoxification , protein synthesis ,and production of biochemicals which are necessary for digestion . Liver is essential for survival ; there is currently no other way to compensate for the absence of it.
This organ plays a major role in metabolism . It lies below the diaphragm in the abdominal pelvic region of abdomen. It produces bile, an alkaline compound  which aids in digestion.
People who drink too much liquor suffer from liver cancer . Liver cancer is the main cause of death in those patients. Some say Hepatitis (Jaundice ) disease also occurs because of infection to liver. 

Wednesday, December 12, 2012

What is Vinegar?

                                             What is Vinegar?

Vinegar is used widely in kitchens nowadays. But actually its an acid.
Vinegar is a liquid substance consisting mainly of acetic acid ( CH3CO2H) and water . It is today widely used in kitchens as a general cooking ingredient . It is the most easily available mild acid . It has a great variety of industrial , medical and domestic uses.
It can also be used as a general household cleanser. White vinegar , since it is acidic , it can dissolve mineral deposits from glass and other smooth surfaces. For most uses , dilution with water is recommended for safety . Vinegar is also used to remove cigarette smoke residue from windows and surfaces .

                                                                                                 

Tuesday, December 11, 2012

What is hard water ?

                                     What is hard water ?

Water described "hard" is high in dissolved minerals especially Calcium and Magnesium . Hard water is not only a health risk but also a nuisance because of mineral build up on fixtures and poor soap and detergent performance as it is hard to get foam.
Water is a good solvent and picks up impurities quickly . As water moves through soil and rock , it dissolves small amount of minerals and holds them in solution. Calcium and Magnesium sulphates are the two most common minerals that make water "hard" .
The degree of hardness becomes greater as the calcium and magnesium content increases. We can add washing soda ( Sodium Carbonate ) to make it to lose its hardness. 

Monday, December 10, 2012

Symptoms that may indicate AIDS

                                         Symptoms that may indicate  AIDS

AIDS is the acronym for Acquired Immuno Deficiency Syndrome .  It is a disease of the human immune system caused by the Human Immunodeficiancy Virus (HIV)
During the initial infection , a person may feel a brief period of influenza like illness . This is typically followed by a prolonged time without symptoms. As the illness progresses , it interferes more and more with the immune system , making people much more likely to get infections.
There is no cure or vaccine for the disease ; however anti retro viral treatment can slow the course of the disease . But these medications are costly and may be associated with side effects. HIV originated in western central Africa during the early twentieth century.
People with AIDS , have an increased risk of developing various virus induced diseases . The patients have systematic symptoms such as prolonged fevers , sweats ( particularly at night ) , swollen lymph nodes , chills , weakness , and weight loss .

Saturday, December 8, 2012

Lunar facts

                                                    Lunar facts

Lunar facts means facts about moon. We all know moon is the natural satellite of earth.
1. We see moon glowing in the sky. But moon isnt producing any light. He is just reflecting the sunrays that fell on him.
2. Lunar eclipse always happen on full moon days.
3.  Only one face of moon is visible from earth as the direction of revolving of both moon and earth are in the same way.
4. Upto 59 % of area of moon is visible from earth.
5 . Moon is going outwards from earth day by day.
6. Astronaut Kalpana Chawla's name has been put to crater of moon.

Friday, December 7, 2012

Hydrochloric acid

                                   Hydrochloric acid

Hydrochloric acid has the chemical formula HCl. It is used in our chemistry labs . It is corrosive and should be handled with care.
The acid can be found naturally occuring in the stomachs of many animals as a relatively weak solution. Excess hydrochloric acid in the stomach may cause dyspepsia. 
Hydrochloric acid does not contain any organic molecules , hence is regarded as a mineral acid. It is an aqueous solution of hydrogen chloride , which when in a saturated form contains about 43 % of hydrogen chloride. The aqueous solution is a strong electrolyte.
It disassociates to give H + and Cl - ions. Ionization is so much complete that the acid is considered as strong acid. Since it is a corrosive acid , it can be used to clean the metal surfaces. It is also a strong electrolyte, proton donor and also an acid.

Thursday, December 6, 2012

Why does it hurt when an ant bite?

                                     Why does it hurt when an ant bite?

If I were to say scientifically , ants do not bite. Ants are not like mosquitoes. Mosquitoes suck the blood but we do not feel pain as they inject anesthetic to numb that area.
But ants dont have that mechanism. Actually , ants dont feed on our blood like mosquitoes. They bite us only for self defense  They spray formic acid    from their tail. This perticular acid hurts. If we are not alive , we would die because of effect of this acid.
Its chemical formula is HCO2H. It is usually found in venom of bee and ant stings.  Formic acid has low toxicity . However concentrated one may kill us.

Wednesday, December 5, 2012

Liquid silver

                                           Liquid silver

Here i am not referring about silver jewellary.  There is an element which is also referred as liquid silver because of its appearance.
It is mercury. It is having the chemical name Hg and atomic weight of 80. It is also known as quick silver or hydrargyrum.  Because of the name hydrargyrum, it has got the chemical name Hg. Mercury is the only metal which is liquid at standard condition of temperature and pressure .
The only other element which is liquid at these conditions is Bromine. The element mercury is toxic. It is widely used in thermometers , barometers , sphygmomanometers etc. It is used in clinical conditions because of its toxic nature . It is also used in amalgam material for dental restoration.
Mercury   is also used in tubelights found in houses . Electricity is passed through mercury vapours in florescent lamps producing short wave ultraviolet light , which then causes the phosphor in the tube to fluoresce, making visible light. 

Tuesday, December 4, 2012

Monkey's day out in our garden

                             Monkey's day out in our garden

After finishing all the tender coconuts in our coconut trees, monkeys were gone to some other place in search of fresh tender coconuts.  But today morning , I spotted a lone monkey in our garden. I shouted at it. It stared at me as if it is not scared of any one.
I wondered why it has come again? It has finished all the tender coconuts in trees. But I didnt see its family members. It was alone. May be other members have asked it to go to our garden and inspect what all left ? what is the new development?
I remembered God  Hanuman has come to Lanka in search of Sita. Similarly , this monkey has come in search of tender coconuts which it has forgotten to pluck and drink !
God Hanuman = Lone monkey spotted in my garden.
Sita = tender coconuts .
Ravan = me !
I am thinking of burning monkey's tail as Ravan did . Now I know exactly what Ravan felt when he saw Hanuman in his country . !

Monday, December 3, 2012

Eagle nest

                                           Eagle nest

As I was walking in garden in the morning time, I observed an eagle busy picking up wooden sticks. But because of the sound made by my crutch , it was alert and carried the sticks in its beak and flew away over my head. I said assuring words but it flew away.
According to my knowledge , the eagle must be preparing tools for its nest. Henceforth , I will call it as pregnant eagle. But if it is pregnant, its stomach must be bulged. But the eagle looked quite normal and it flew normally too.
I remembered the wordings of book regarding birds : only the mammals' stomach will get bulged when they are pregnant. Like humans  and other animals. Pregnant eagle usually lays 2 eggs in its nest. Its nest usually situated in higher positions like our pregnant eagle had selected a coconut tree !
In eagles , it is female domination. Female species are much stronger compared to male . But both , male and female look after the eggs , the other one will be off to food fetching. Out of 2 eggs it has put , if one of them is male and the other one is female , they will fight as soon as they born, and female will be victorious and it will kill its brother infront of parents !

Saturday, December 1, 2012

How does fog form?

                                  How does fog form?

In morning, I could see fog in the surroundings of my house. In the place of high humidity , like ours ,  fog is formed. Tiny water droplets are also dropping on the head.
Fog is a natural weather condition that can cause visibility to become zero. In some places, (not ours !) schools delay their opening time,  until the Sun burns fog off.
How does the fog form ? Fog is basically a cloud on the ground. These clouds are the collection of tiny water droplets formed when evaporated water is cooled. The infrared cooling is responsible for the fog formation .
Infrared cooling is formed due to the change of seasons from summer to fall and winter.  During the summer , the ground absorbs solar radiation. As air passes over it, it is made moist and warm. This mass of warm air collides with cooler air.
This cause the water vapour in the air mass to condense quickly  and fog is formed.