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Wednesday, February 10, 2021

How is a rainbow formed ? | Natural Hub

  The Sun and a wet weather are the main components of the Rainbow. When the sunlight with its white light rays cross the water drops, the different colours that constitute the white light split up, to be scientifically accurate, the colours are refracted, thus forming a rainbow. White light is refracted through the drops of water which displays all the colours, but the human eye can only see one colour per drop, and that is why the height of the drops is a crucial determinant in the order of the colours which is always respected. The highest drops to the outside allow us to see red, while the lowest drops inward allow us to see purple. Between red and purple, we see the orange, yellow, green, blue and indigo colours in that order which makes the seven colours of the rainbow. The more the drops of water are big, the more the rainbow is colorful. Nature never ceases to amaze us, we need to uncover its mysteries that surround us...


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How much does a cloud weigh ? | Natural Hub

 Clouds come in many forms and weights.


A weight that depends on three essential factors : size, temperature and the water content called density.


Scientists estimate that a small cloud can weigh more than 500 tons of water.


But what’s frightening is the clouds that cause thunder, they can reach a weight of 500,000 tons and even more in regions where rainfall is intense, such as tropical areas.


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How is rain formed ? | Natural Hub

 The liquid precipitation from the sky, called rain, is the result of the evaporation of moisture that exists in nature and specifically in different sources of liquid such as seas, lakes, rivers, oceans...


Clouds form when evaporated water is condensed into liquid water. The presence of small particles in the air facilitates and helps the formation of droplets and that’s how a cloud is formed.


The inside of a cloud composed of a mixture of moist air and water droplets is the scene of several formations, droplets move at different speeds and multiple directions, sometimes colliding with each other, and that is how the droplet increase in size and bigger drops are formed.

Once, the drops are large enough, Earth's gravity takes over and the drops fall on the surface of the Earth as precipitation, namely rain.


The rain is a blessing from heaven, and especially after a dry season.

Our water supplies depend on precipitation and especially our crops.

Water is a source of life, we must take good care of it.


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Where does the colours of the sky come from at sunset ? | Natural Hub

 Sunset is a magical moment that reveals one of nature's wonders.

Why does the sky lose its blue colour and give way to this red-orange one that we are so fascinated about?


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Tuesday, February 9, 2021

Views of psychoanalyst on Racism

Awareness of racism increased as Black Lives Matter protests spread across the country last summer. In response, psychoanalysts suggest three ways to change attitudes about race — curiosity, courage, and building intimate relationships with others.Curiosity starts with self-education and self- reflection to better understand our beliefs as well as talking to others about ethnicity and racism.Courage is necessary to confront our own unacknowledged biases and recognize where some of them come from, including our upbringing or involvement in various groups, or from society at large.Finally, one of the most profound ways of changing attitudes about others is engaging in close relationships with people from other ethnicities. Building and maintaining relationships with individuals of differing backgrounds allows recognition of our common humanity and shared struggles.However, experts point out that being aware of, acknowledging, and changing deeply-ingrained racist ways of thinking is difficult and takes time and effort.The human mind resists change to protect our self-esteem from uncomfortable truths, and our minds unconsciously work diligently to avoid uncovering painful and distressing knowledge about ourselves. Even making change we know will make us feel better, such as exercising more, can be hard to initiate and sustain."Often, changes to how we think or do things require a shift in how we view ourselves, our needs, and our relationships," says Deeba Ashraf, MD, member of the American Psychoanalytic Association (APsaA). 

"And changing attitudes about race can be especially hard because these attitudes are usually learned when we are very young."Beverly J. Stoute, a child and adolescent psychoanalyst and psychiatrist, says children develop awareness of and curiosity about racial differences early. 

"As children grow, parents, teachers, media representations, and interactions with different groups can either powerfully facilitate or thwart children’s openness to racial and ethnic differences," said Dr. Stoute, also a member of APsaA.There are many ways we try to protect ourselves from painful feelings or unwanted truths about our own beliefs. One way is by asserting that unpleasant truths are not real, otherwise known as denial. Another way is to imagine these "horrible truths" only exist in others and not in ourselves. 


This is called projection and it involves attributing qualities like laziness or criminality to a particular group; while overlooking how these traits might apply to ourselves, or those in our own group.Hence, "group identity," also presents a challenge to changing attitudes about racism. Being part of a group can offer a sense of connection and protection, and in some cases, prestige. Many group identity attitudes are passed on from generation to generation, but also part of ongoing relationships with others who share the same ideas. Trying to change an entrenched attitude can result in group members feeling threatened or fearing a loss of group membership, according to APsaA experts.


Yet, when people can break through these unconscious ways of protecting their self-image, they may recognize the costs of racism and look at the loss and pain it inflicts on oneself and others. It may be possible to reevaluate one’s own ideas of what is healthy and growth-oriented.

 This process can be difficult, but managing the discomfort these efforts provoke can motivate a desire to change, psychoanalysts say."I am reminded of a quote from James Baldwin, ‘People can cry much easier than they can change’," says Ebony Dennis, PsyD, clinical psychologist and psychoanalyst who is also an APsaA member. "Changing attitudes about racism will take time and effort, and occasionally some hurt feelings. But it is through these growing pains that real, lasting change happens."

At what temperature wood burns ? | Natural Hub

 Self-ignition of materials without external ignition source differs from one material to another.


For wood, its self-ignition point is 300° C.


Heated to this temperature, wood releases hydrocarbons which when mixed with atmospheric oxygen causes a reaction that ignites wood.


To cite just one example, cotton has a higher resistance which is located around 407° C.


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What’s a lightning bolt ? | Natural Hub

 During bad weather, children and adults alike dread the deafening sound of thunder when they see lightning in the sky.


This climatic phenomenon happens during storms.

Huge masses of air move and gain electricity charge by friction resulting in the accumulation of several charges in the huge black clouds.


The water molecules go up and get positive charges while the heavy water molecules remain at the base and get negative charges.


When the electrical load is too large, a discharge of lightning occurs between the areas of opposite charges, causing a huge spark and thus lightning in all its beauty is formed.


Lightning can occur between clouds and the ground or inside the cloud in several forms, it can be branched, fulminated or sinuous...


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Can a drought trigger a flood ? | Natural Hub

 Drought can be one of the essential causes of the floods if, and only if, it is followed by heavy rains.


Drought drains rivers and lakes, of which the soil becomes dry and solid.


The large amounts of water from heavy rain accumulates on the surface of the earth and is unable to infiltrate the soil, resulting in areas submerged by water which leads to the flood.


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Monday, February 8, 2021

The Icebergs and their secrets | Natural Hub

 An iceberg is a block of ice floating on the surface of the ocean, seas, and even lakes.  This glacier, which can range in size from a few centimeters to several thousand kilometers long, has broken away from the mainland in the polar regions, splits and drifts over vast expanses of water as the sea currents and winds flow.  An iceberg is caused by the accumulation and settlement of snow on the mountains and glaciers in the pack ice over thousands of years. Most icebergs are made up of fresh water that takes a long time to thaw, which is why they melt very slowly and last quite a long time.  The iceberg always occurs as a visible area above the water, the emerged surface represents only 10% of the block and it is the submerged area that represents 90% that is the most dangerous, given its quite different shapes.  A cautionary saying : only the tip of the iceberg is known.


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What is a volcano ? | Natural Hub

 Thousands of kilometers underground, it is very hot, so hot that the rock melts away from its organic state to its liquid state.


The liquid flowing from the rocks and mixing with different gases that the earth abounds in, forms magma.


The magma, an essential component in the formation of a volcano, travels tens of kilometers from the earth's surface, creating a pathway through the cracks caused by warming in the Earth's crust.


The accumulation of magma forms the magma chamber, which can remain at rest for decades, but under the effect of a large number of molten rocks, the magma pushes the ceiling to the surface and then turns into a volcanic eruption.


When it reaches the surface, the very hot magma in contact with much colder air becomes thicker and forms the lava that flows through the volcano and gradually cools and turns into rock.


The volcano can be on land or underwater.

It is very dangerous and quite destructive and examples in history are numerous...


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Sunday, February 7, 2021

What is a solar eclipse ? | Natural Hub

 In the universe, everything is in motion.

The moon revolves around the earth, which itself revolves around the sun.


An eclipse is the alignment of the sun, moon and earth with the moon in the middle.


At this precise moment, the sun is hidden by the moon and its light does not reach the earth, so the inhabitants who are in this alignment will then observe the dark side of the moon, this is the extraordinary phenomenon of the solar eclipse that we do not have the chance to see often and which only lasts for a short time since the main actors are always in motion, namely : the Sun, the Moon and the Earth.


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Why do trees lose their leaves in autumn ? | Natural Hub

 Nature has given trees the means to defend themselves against bad weather, but is that enough?


Trees in autumn adapt to the cold, the trunk protected by the bark, the roots by the soil, only the leaves are confronted with the rigor of the climate.


The drop in temperature and the decrease in warmth time mean that the leaves no longer receive sap, which is an essential nutrient for the survival of the leaves.

The leaves then feed on their provisions, before dehydrating, hardening and eventually falling.

The color of the leaves deteriorates as the sunlight is reduced, which mainly influences deciduous leaves.


Unlike deciduous leaves, evergreen leaves in conifers such as pine, cedar or spruce keep their leaves because they are needle-shaped or flake-shaped and have much smaller exposure surfaces.


Deciduous leaves are more allergic to cold than evergreens, which resist better by keeping their autumn robes.


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Tuesday, February 2, 2021

58 Tips to make learning easy, quick and effective( How to pass examination with good percentage)

Simple techniques to secure first rank and pass entrance examination


"One day, all your hard work will pay off"

"The earlier you start working on something, the earlier you will see results."

"You don’t have to be great to start. But you have to start to be great."

"We generate fears while we do nothing. We overcome these fears by taking action"

1)Ask questions: Clear your queries and doubts.Talk to teacher and subject experts.


2) Make your own notes.

3)Make study time table.Follow it religiously

4) Set target of the day

5) Study regularly...No off days

6)Keep record of your progress

7) Learn important and relevant content

8) Solve previous years question papers

9)Avoid distraction

10) Exercise Regularly

11) Proper and adequate light in study room

12) Summarize content

13) Solve model papers

14)Sleep for 8 to 9 hrs ( at a stretch)

15)Focus on weak areas

16)Practice Perseverance

17)Be consistent

18)Have balanced diet

19) Include dates, almond, Indian gooseberry, eggs, milk, meat walnut ...in your diet

20) Go to sleep early

21) Drink adequate water

22)Divide tasks and strive hard to achieve it

23) Set Priorities ( important topics first)

24)Take short breaks after every two hours

25)Don't take stress

26) Do relaxation exercise

27)Study everyday...Revise regularly

28) Drill important definitions and formula

29)Display important formulas in your room

30)Revise content after class

31) Learn through audio visual aids

32) Explain answer and concepts to your friends

33)Read and understand textbook thoroughly 

34)Avoid last moment study

35) Night is for rest

36) Early to bed, early to rise make man Healthy, Wealthy and Wise

37) Face examination before actual examination..practice.. practice...as per alloted time and difficulty level

38) Compete with yourself

39)Don't waste time

40)Don't have fear of examination

41)Apply acquired in day to day life situation

42) Avoid rote learning

43) Understand ... Understand

44)Pay attention in class

45)Make flow chart and sketch to remember process and points

46) Take Bath

47) Splash water on your face and eyes after regular intervals

48) Be organized: Keep all required materials pen, calculator, book, study material, pencil, scale, graph paper..at one place ...Don't waste time in searching them

49)Be positive

50) Self assessment: Ask questions to your self


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1) Set Study Goals

There is lots of credible research suggesting that goal setting can be used as part of a strategy to help people successfully effect positive changes in their lives, so never underestimate the power of identifying to yourself the things you want to achieve. Just make sure to ask yourself some key questions: Am I setting realistic goals? Will I need to work harder to achieve those goals? If you’re happy with the goals you’ve set then you should aim to develop your study plan for the year ahead with your goals in mind.


2) Make a Study Plan

Time is precious. Nobody is more aware of this than the poor student who hasn’t studied a thing until the night before an exam. By then, of course, it’s too late. The key to breaking the cycle of cramming for tests is to think ahead and create an effective study plan. Not only will this help you get organised and make the most of your time, it’ll also put your mind at ease and eliminate that nasty feeling you get when you walk into an exam knowing that you’re not at all prepared. As the old saying goes, fail to prepare and be prepared to fail.


3) Take Regular Study Breaks

None of us are superhuman, so it’s important to realise that you can’t maintain an optimum level of concentration without giving yourself some time to recover from the work you’ve put in. This can take the form of a ten-minute walk, a trip to the gym, having a chat with a friend or simply fixing yourself a hot drink. If it feels like procrastination, then rest assured that it’s not: taking regular short breaks not only help improve your focus, they can boost your productivity too.


4) Collaborate with Study Partners

At this stage of the school year, you should know your classmates pretty well. This is a good point in time to select a couple of study partners who you know you work well with and are motivated to achieve good grades also.


5) Turn lessons into stories

Everybody likes to read or listen to a good story, and with good reason – not only do stories entertain us, they help us to understand and memorise key details too. You can apply this to your studies by weaving important details or facts into a story – the more outlandish and ridiculous you can make it, the better(since you’ll be more likely to remember a particularly crazy story).


6) Establish a Study Routine

Your study routine is comprised of more than planning what to learn and when. One of the main concerns is your study environment.ind a place to study that is quiet and with few distractions. Alternatively, you could also try switching it up by sitting in a different place in your school library every day and seeing how this works for you.


7) Mark Small Challenges

When you have to face very long and dense subjects, you can set small challenges to keep your spirits high; a good way to focus on the day-to-day and find motivations while you study. According to scientific analysis, the more motivated and excited we are, the better our brain performs.




8) Consult teachers

Any questions you have about the exam, the best you can do is go to the teacher of the subject and expose your doubts. Not only is the person best suited to solve your questions, but your initiative will be well received and you’ll show good attitude by demonstrating that you’re interested in his subject.


There really aren’t any hard and fast rules to play by when it comes to best times for studying or how long you should work for. Everybody is different, so the best way to establish a routine is to try different things and see what works best for you, then modify your routine for maximum learning effectiveness