Competition ZENITH

Why is rainbow seen after rain? After a rainfall, the clouds break and lie hanging in the sky and the sun is also visible. The Sun’s rays, falling on the water drops, are dispersed, totally reflected at the back of the drops and then again refracted into the eye of the observer with his back towards the sun. These dispersed rays which have suffered deviation give rise to a concentrated beam of light indicating all the colours of light. Ice wrapped in a blanket or packed with saw dust does not melt away quickly. Why? Ice wrapped in blanket does not melt, because blanket being bad conductor, cut off heat rays. Saw dust is also a bad conductor of heat. It protects the ice from the external heat and prevents it from melting away. Petrol fire cannot be put with water. Why? Petrol has less density than water. So when water is poured the petrol floats on it and keeps on burning.The temperature of the burning petrol is so high than the water and it would be evapora...

“Father of Geography” – Eratosthenese   (Ist to measure earth circumfrence) “Systematic Geography” – Alexander Von Humbolt “Regional Geography” – Karl Ritter Origin & Evolution of Earth Ist Argument – Immanuel Kant (Germany) “Nebular Hypothesis” & “Binary Theories” – Laplace (1796) Modern Theory “Father of Big Bang Theory” - Georges Lemaitre (Belgium), Propounded by Edwin Hubble (1920) “Steady State Theory” - Hoyle  The solar system consists of the Sun and 8 planets revolving around it in different orbits. The statistics of the sun and the planets are given below: SUN •Age : About 5 Billion years •Distance : 149.8 Million Kms •Diameter : 1,38,400 Kms. •Photosphere temperature : 5,770 K •Core temperature : 150,000,000 K •Absolute visual magnitude : 4.75 •Rotation (as seen from the earth at the equator) : 25.38 days •Rotation (near the poles) : 33 days •The sun consists of 71% of Hydrogen, 26.5% Helium...

1.  Archimede's principle  - It states that a body when wholly or partially immersed in a liquid, experiences an upward thrust which is equal to the weight of the liquid displaced by it. Thus, the body appears to lose a part of its weight. This loss in weight is equal to the weight of the liquid displaced by the body. 2.   Aufbau principle  - It states that in an unexcited atom, electrons reside in the lowest energy orbitals available to them. 3.  Avogadro's Law  - It states that equal volumes of all gases under similar conditions of temperature and pressure contain equal number of molecules. 4.  Brownian motion  - It is a zigzag, irregular motion exhibited by small solid particles when suspended in a liquid or gas due to irregular bombardment by the liquid or gas molecules. 5.  Bernoulli's principle  - It states that as the speed of a moving fluid, liquid or gas, increases, the pressure within...

Gravitation is the force of attraction between two objects in the universe. Gravitation may be the attraction of objects by the earth.    e.g.,  a) If a body is dropped from a certain height; it falls downwards due to earth’s gravity. b) If a body is thrown upwards, it reaches a certain height and then falls downwards due to the earth’s gravity.

Brought to you by - Competition ZENITH  Work: Work is said to be done if a body gets displaced when a force is applied on it. It is measured by the product of force and displacement of the body along the direction of force. If a body gets displaced by ‘d’ when a force ‘F’ acts on it, then Work ‘W’,                                                           W = F cosθ×d  where , θ  = angle between force and displacement. Work is a scalar quantity. SI unit = joule. Energy: Capacity of doing work. It is a scalar quantity . SI unit = joule.