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The outer surface of a beaker containing ice cubes becomes wet in short while - Give scientific reason.

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Question  The outer surface of a beaker containing ice cubes becomes wet in short while. Answer  When ice cubes are placed in a beaker, ice starts melting.  The heat required for melting is absorbed from the surrounding air and also from the beaker to some extent.  Hence, the temperature of the air and beaker falls.  The capacity of air to hold water vapour depends upon the temperature of the air, and this capacity decreases as the temperature decreases.  At a certain low temperature, the surrounding air becomes saturated with water vapour present in it.  As the temperature falls further, the air is unable to hold all the water vapour.  Hence, the extra water vapour starts condensing on the cold outer surface of the beaker in the form of minute drops.  Therefore, The outer surface of the beaker containing ice cubes becomes wet in a short while.
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The outer surface of a beaker containing ice cubes becomes wet in short while - Give scientific reason.

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Question  The outer surface of a beaker containing ice cubes becomes wet in short while. Answer  When ice cubes are placed in a beaker, ice starts melting.  The heat required for melting is absorbed from the surrounding air and also from the beaker to some extent.  Hence, the temperature of the air and beaker falls.  The capacity of air to hold water vapour depends upon the temperature of the air, and this capacity decreases as the temperature decreases.  At a certain low temperature, the surrounding air becomes saturated with water vapour present in it.  As the temperature falls further, the air is unable to hold all the water vapour.  Hence, the extra water vapour starts condensing on the cold outer surface of the beaker in the form of minute drops.  Therefore, The outer surface of the beaker containing ice cubes becomes wet in a short while.
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A plastic bottle, completely filled with water, when kept in a freezer, is likely to break - Give scientific reason.

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Question A plastic bottle, completely filled with water, when kept in a freezer, is likely to break Answer  The temperature of air in the freezer (deep freeze) compartment of refrigerator is less than 0 degree C.  When a plastic bottle, completely filled with water, is kept in this compartment, the temperature of water falls below 4 degree C and the water expands.  Even when water freezes and ice is formed, there is an increase in the volume.  It exerts a large pressure on the sides of the  bottle and hence the bottle is likely to break.
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When you enter a warm room after being outside on a frosty early morning, your spectacles 'steam up' - Give scientific reason

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Question  When you enter a warm room after being outside on a frosty early morning, your spectacles 'steam up'  Answer  On a frosty early morning, the temperature of air outside warm room is lower than the dew point.  Hence, When you enter the room from outside, some water vapour in the room condenses on the glass of your spectacles, i.e., the spectacles 'steam up'.
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Water droplets are seen on the outer surface of a cold drink bottle - Give scientific reason.

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Question Water droplets are seen on the outer surface of a cold drink bottle. Answer  The temperature of the outer surface of a cold drink bottle is less than that of the atmosphere.  Therefore, the excess of water vapour from the air condenses to form droplets onn the outer surface of the cold drinks. 
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In cold countries, in winter, even when the water of lakes freezes, aquatic animals and plants can survive - Give scientific reason.

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Question  In cold countries, in winter, even when the water of lakes freezes, aquatic  animals and plants can survive. Answer In cold countries, in winter, a layer of ice is formed on the surface of lakes when the atmospheric temperature falls below 0 degree C.  However, below this layer, there is water at 4 degree C. Ice, being a bad conductor of heat, does not allow transfer of heat from this water to the atmosphere. Hence, aquatic animals and plants can survive in this water.
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If crushed ice is pressed and then the pressure is released, a lump of ice is formed - Give scientific reason

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Question If crushed ice is pressed and then the pressure is released, a lump of ice is formed Answer  When crushed ice is pressed, its melting point is lowered and some ice melts to form water. When the pressure is released, the melting point becomes normal and the water freezes to form ice forming a lump. 
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In winter the pipelines carrying water burst in cold countries - Give scientific reason.

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Question  In winter the  pipelines carrying water burst in cold countries Answer  In cold countries, in winter, the temperature of the water falls below 0 degree C.  When the temperature of water falls below 4 degree C, it expands.  Hence, the water in pipes expands.  Even if ice is formed, there is an increase in the volume.  As there is no room for expansion, water (or ice) exerts a large pressure on the pipes.  Hence, the pipelines carrying water burst.
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Even Though heat is supplied to boiling water, there is non increase in its temperature - Give scientific reason.

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Question Even Though heat is supplied to boiling water, there is non increase  in its temperature Answer  Once water starts boiling, all the heat supplied to its used in conversion of water into steam at the boiling point of water.  Hence, there is a no raise in its temperature.
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Burns from steam are worse those from boiling water at the same temperature- Give scientific reason

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Question Burns from steam are worse those from boiling water at the same temperature Answer  A given quantity of steam contains more heat than the same quantity of boiling water at the same temperature.  When steam comes in contact with one's body, it releases extra heat of 540 calories per gram and causes a more serious burn than that caused by boiling water.
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The material used for fuse has low melting point or A fuse should be made of material of low melting point - Give scientific reason.

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Question The material used for fuse has low melting point or A fuse should be made of material of low melting point Answer A fuse is used to protect a circuit and the appliances connect in the circuit by stopping the flow of an excessive electric current. For this, a fuse is connected in series in the circuit. When the current in the circuit passes through the fuse, its temperature increases. When the current exceed the specified value, the fuse must melt to break the circuit. For this, the material used for a fuse has low melting point.
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With a specific initial velocity, we can jump higher on the moon than on the earth, give scientific reason.

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Question What is Gravitational Force What is the value of g GIVE REASON : With a specific initial velocity, we can jump higher on the moon than on the ea rth.               Answer what is High and low tides what is weightlessness in space Gravitational waves  The acceleration due to gravity on the moon is 1/6 of that on the earth. Hence, with a specific initial velocity, we can jump higher on the moon than on the earth. This can be seen from the equation h=u^2/2g. Other Questions like this  (1) The weight of an object changes from place to place though its mass is constant. (2)   If a feather and a stone are released from the top of a building simultaneously, the stone reaches the ground earlier than the feather .
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What is an Ellipse

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  An Ellipse               Do You Know: An ellipse INFORMATION:  what is High and low tides   What is the value of g Gravitational waves  what is weightlessness in space                             An Ellipse is the curve obtained when a cone is cut by an inclined plane. it has two focal points. The sum of the distances to the two focal points from every point on the curve is constant. F1 and F2 are two focal points of the eliipse shown in upper figure A,B and C are three points on the ellipse then, What is Gravitational Force                                     AF1+AF2=BF1+BF2=CF1+CF2 Other posts: What is Newlands' law of octaves Unheard Points of chemical reaction  Disaster Information Disaster Management Disaster Management Authority Ecosystem Effect of water poll...
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Weightlessness In Space Information

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 The Weightlessness In Space  Gravitational waves     DO YOU KNOW: THE WEIGHTLESSNESS IN SPACE What is the value of g What is Gravitational Force INFORMATION:                           Space travellers  as well as objects in the spacecraft pppear to be floating. Why does this happen? though the spacecraft is a height from the surface of the earth, the value of 'g' there is zero(0).                             In the space station the value of 'g' is  only 11% less than it's value on the surface of the Earth. Thus, the height of a spacecraft is not the reason for their weightlessness. their weightlessness is caused by their being in the state of free fall.                            Though the spacecraft is not falling on the earth because of...
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What is the Low And High Tides

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Low And High Tides   What is the value of g Gravitational waves  What is Gravitational Force                                 Do You Know: Low And High Tides INFORMATION:-  what is weightlessness in space                             You must be knowing about the high and low tides that occur regularly in the sea. The level of sea water at any given location along sea shore increases and decreases twice a day at regular intervals. high and low tides occur at different types of water in the sea changes because of the gravitational force exerted by the moon.                              Water directly under the moon gets pulled towards the moon and the level of water there goes up causing high and low tide at that place. At two places on the earth at nine...
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The Value of 'g' Information

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The Value Of 'g' what is weightlessness in space                                               DO YOU KNOW: THE VALUE OF 'g' INFORMATION:-   What is Gravitational Force                         The value of g is the same for all object at a given place on the earth. thus, any two objects, irrespective of their masses or any other properties, when dropped from the same height and falling freely will reach the earth at same time. Galileo is said to have performed an experiment around 1590 in the Italian of Pisa. He dropped two spheres of different masses from the learning tower of Pisa to demonstrate that both spheres reached the ground at the same time. what is High and low tides   Gravitational waves                          when we drop a ...
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Gravitation force

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  Gravitational Force what is High and low tides   The phenomenon of a gravitation was discovered by Sir Issac Newton. As the story goes, he discovered the force by seeing an apple fall from a tree on the ground. He wondered why all apples fall vertically downward and not an angle to the vertical. Why do they not fly in a horizontal direction? Gravitational waves  After much thought, he came to the conclusion that the earth must be attracting the apple towards itself and this attractive force must be directed towards the center of the earth. The direction from the apple on the tree to the center if the earth is vertical direction at the position of the apple and thus, the apple falls vertically downwards. what is weightlessness in space On the up side shows an apple tree on the earth. The force on an apple on the tree is towards the center of the earth i.e. along the perpendicular from the position of the apple to the surface of the earth. The figure also shows the gravit...
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Gravitational Waves Information

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  The Gravitational waves   what is High and low tides             Do You Know: THE GRAVITATIONAL WAVES INFORMATION:-                                              Waves are created on the surface of water when we drop a stone into it. Similarly you must have seen the waves generated on a string when both its end are held in hand and it is shaken. Light  is also type of wave called the ELECTROMAGNETIC WAVE. Gamma rays, X-rays, ultraviolet rays, infrared rays, microwaves and radioactive waves are all different types of ELECTROMAGNETIC WAVES. Astronomical objects emit these waves and we receive them using our instruments. What is the value of g What is Gravitational Force                     Gravitational waves are a very different types of waves. They have been called the waves on ...
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Disaster Information

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 Disaster                                       Do you know: Disaster INFORMATION: Some basics points                                Variously dangerous events occur many times in the environment. Those are called as Disaster. Some of the main natural disasters are floods, wet and dry famine, cyclone, earthquakes, volcanoes, etc. These are 'all of a sudden' troubles to the mankind. such events cause sudden changes in the environment and thereby cause the damage to it. Environment is also damaged due to use of natural resources for our development. This leads to sudden disaster. Un expected to human. This can called man made disaster.                                        United nations has defined the disa...
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Effects of water pollution and soil pollution

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Effects of water pollution 1)Pathogenic and non pathogenic organisms are present in polluted drinking water. 2)Water born disaster such as cholera, typhoid, diarrhea, dysentery, hepatitis, polio, and  jaundice can be caused due to pathogens. 3)Water pollution affect on aquatic life. a) Oil pollution affect algae. b) Reduction in dissolved oxygen can kill fishes. c) Pesticides affect reproduction and growth of fishes. d) Detergents cause harm to the respiratory system of fishes. Effects of soil pollution  1) Soil erosion retarded growth of plants/crops. 2)Nutrition deficiency. 3) Loss of fertility and productivity of soil. 4) Sewage sludge containing harmful bacteria can cause infections and diseases. 5) Radio active soil pollutants can enter into crops, animals and humans through the food chain.
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Ecosystem

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Ecosystem                       The abiotic and abiotic factors and their interaction from an ecosystem. Producers like plants are important Herbivorous, Predators like lion and tiger also equally important and also the termites, insects present in dung that are decomposers are also the termites, insects present in dung that are decomposers are also important for our existence.
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