CSS, PCS, ISSB and other Competitive examination preparation

Why is Venus hotter than Mercury if Mercury is closer to the sun? This is a great question! The answer to it lies in the fact that Venus has a very dense atmosphere made up of carbon dioxide, nitrogen, and sulfuric acid, while Mercury has a very thin atmosphere with various gases, but very little carbon dioxide. So what's so important about carbon dioxide? Well, sunlight will pass through Venus' clouds (which contain mostly carbon dioxide) and warm the surface of the planet. Usually, the surface of a planet is warmed during the day and cools off at night by releasing infrared radiation (heat) back into space. But the carbon dioxide in Venus' clouds absorbs energy from infrared radiation very well and "traps" the heat on the planet, making it very warm. This has sometimes been called a "runaway greenhouse effect." We don't see this happen on Mercury because its atmosphere is not thick and does not have much carbon dioxide in it. I hope ...

Benefits of Inverter Air Conditioning Inverter air conditioning  is more expensive than non inverter air conditioning but with the current spiralling energy costs, is it worth the extra ££s? Let's see what are the benefits of an inverter air conditioning compared with a non inverter air conditioning:- At least 30% - 50% cheaper to run as it consumes less power Far quicker to achieve desired temperature The start up time is reduced by 30% Much quieter No temperature fluctuations, maximising comfort level No voltage peaks from compressor All EcoAir inverter air conditioning are heat pumps which in itself is one of the most energy efficient form of heating Is it worth paying more for an inverter air conditioning?  So, in summary an inverter air conditioning can reduce your energy bill.  It will be worth paying more for an inverter air conditioning if you use your air conditioning for:- all year round used for heat...

Scientific research conducted explained that water, has it's own memory, its own distinction and own characteristics when it comes to remembering a thing. They researched and found that, it was water memory, when they put a flower in it the microscopic view of water drop showed the pattern related to it. they conducted another experiment with water and this time changed the flower specie and it, the water, took the shape of the pattern. on a conclusive end it was said that when a person drinks a water the memory of water is transfered into brain at some area and is stored in shape of neurons. wherever water goes it picks up information. so the water has more information at the mouth of the lake then on the source.    This scientific discovery further explained that oceans are like gigantic store house of information, in years to comes they would act as a connection bridge between civilizations and species.    WATER AND SOUND...

Was Einstein a slow learner as a child? Einstein was slow in learning how to speak. His parents even consulted a doctor. He also had a cheeky rebelliousness toward authority, which led one headmaster to expel him and another to amuse history by saying that he would never amount to much. But these traits helped make him a genius. His cocky contempt for authority led him to question conventional wisdom. His slow verbal development made him curious about ordinary things — such as space and time — that most adults take for granted. His father gave him a compass at age five, and he puzzled over the nature of a magnetic field for the rest of his life. And he tended to think in pictures rather than words.

The idea of duality originated in a debate over the nature  of  light  and  matter  that dates back to the 17th century , when  Christian Huygens  and  Isaac Newton  proposed  competing theories of light:  light was thought either to consist of waves (Huygens) or  of  particles  (Newton). Through the work of  Max Planck ,   Albert Einstein ,  Louis de Broglie ,  Arthur Compton , Niels Bohr ,   and many others, current scientific theory  holds that  all  particles  also  have a wave nature (and vice versa)

What does nuclear fission have to do with the birth of stars? Fission has nothing to do with it. Fusion does, however. Fission is the process by which large nuclei (like Uranium) split apart releasing energy. Fusion is the joining of nuclei to make larger nuclei, with the release of energy. A ball of contracting interstellar gas becomes a star like the Sun when fusion reactions start in its center. Then, we say "a star is born."

Why do some stars end up as black holes? The answer involves the gravity and the internal pressure within the star. These two things oppose each other -- the gravitational force of the star acting on a chunk of matter at the star's surface will want to cause that matter to fall inward, but the internal pressure of the star, acting outward at the surface, will want to cause the matter to fly outward. When these two are balanced (i.e., equal in strength) the star will maintain its size: neither collapse not expand. Such is the case for the Sun at the moment, and even, for that matter, for the Earth.

What is your definition of a quasar?  This is best answered with history. When radio telescopes were first turned on the heavens, point sources of radio waves were discovered (along with spread-out regions of emission along our Milky Way). Astronomers using ordinary visible-light telescopes turned toward these radio points and looked to see what was there. In some cases a supernova remnant was found, in others, a large star-birth region, in others a distant galaxy. But in some places where point sources of radio waves were found, no visible source other than a stellar-looking object was found (it looked like a point of like --- like a star does).

While the universe is a big place to study, we shouldn't forget our own backyard. With eight planets and a wealth of smaller worlds to look at, there's more than enough to learn for a few lifetimes! So what are some of the most surprising things about the  planets ? We've highlighted a few things below. 1. Mercury is hot, but not too hot for ice The closest planet to the Sun does indeed have ice on its surface. That sounds surprising at first glance, but the ice is found in permanently shadowed craters—those that never receive any sunlight. It is thought that perhaps comets delivered this ice to Mercury in the first place. In fact, NASA's MESSENGER spacecraft not only found ice at the north pole, but it also found organics, which are the building blocks for life. Mercury is way too hot and airless for life as we know it, but it shows how these elements are distributed across the Solar System.

i do bot own any text it is taken from encyclopedia bratanica and posted now by rana muddasar as for education purpose. Supernova ,  plural  supernovae  or  supernovas ,  any of a class of violently exploding  stars whose  luminosity  after eruption suddenly increases many millions of times its normal level. The term  supernova  is derived from  nova  (Latin: “new”), the name for another type of exploding  star . Supernovae resemble novae in several respects. Both are characterized by a tremendous, rapid brightening lasting for a few weeks, followed by a slow dimming. Spectroscopically, they show blue-shifted emission lines, which imply that hot gases are blown outward. But a supernova explosion, unlike a  nova  outburst, is a cataclysmic event for a star,

Big Bang Theory - The Premise The Big Bang theory is an effort to explain what happened at the very beginning of our universe. Discoveries in astronomy and physics have shown beyond a reasonable doubt that our universe did in fact have a beginning. Prior to that moment there was nothing; during and after that moment there was something: our universe. The big bang theory is an effort to explain what happened during and after that moment. 

This material (including images) is copyrighted!. See my copyright notice for fair use practices. Select the photographs to display the original source in another window. Links to external sites will be displayed in another window. All galaxies began forming at about the same time approximately 13 billion years ago. The origin of galaxies and how they changed over billions of years is an active field of research in astronomy today. Models for galaxy formation have been of two basic types: "top-down" and "bottom-up". The "top-down" model on the origin of the galaxies says that they formed from huge gas clouds larger than the resulting galaxy. The clouds began collapsing because their internal gravity was strong enough to overcome the pressure in the cloud. If the gas cloud was slowly rotating, then the collapsing gas cloud formed most of its stars before the cloud could flatten into a disk.

  A Brief History of Time attempts to explain a range of subjects in cosmology, including the Big Bang, black holes and light cones, to the nonspecialist reader. Its main goal is to give an overview of the subject but, unusual for a popular science book, it also attempts to explain some complex mathematics.

In August 2006 the International Astronomical Union (IAU) downgraded the status of Pluto to that of  "dwarf planet."  This means that from now on only the rocky worlds of the inner Solar System and the gas giants of the outer system will be designated as planets. The “inner Solar System” is the region of

Teleportation, time machines, force fields, and interstellar space ships—the stuff of science fiction or potentially attainable future technologies? Inspired by the fantastic worlds of  Star Trek, Star Wars,  and  Back to the Future , renowned theoretical physicist and bestselling author Michio Kaku takes an informed, serious, and often surprising look at