Life Sciences Glossary: Relativity Theory: Propounded by Albert Einstein

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Relativity Theory

  • It was propounded by Albert Einstein, first as the Special theory in 1905, then as the General theory in 1915. Two consequences of the special theory are that mass and energy are interchangeable according to a simple mathematical relationship (E = ) , and that the mass of a body increases with its speed. These theories helped resolve contradiction between certain observed facts and certain accepted theories. They fitted anomalies of certain observed astronomical facts into a general law that had no exceptions.
  • It is dangerous to sleep in an unventilated room with fire burring inside because the fire produces Carbon monoxide and Carbon dioxide gases. Carbon monoxide is poisonous and can caused death.
  • The filament of an electric bulb made of Tungsten because it has a high melting point and can be heated to a high temperature to emit light.
  • Water kept in an earthen pitcher becomes cold because the pitcher has minute pores on its surface which absorb water. Water in the pores evaporates when it comes in contact with air and produces a cooling effect.
  • A sliced apple, when exposed to air, turns brown after sometimes as it contains iron which gets oxidized and gives the fruit a brownish colour.
  • The freezing compartment inside a refrigerator is at the top because the air in contact with it becomes cold and heavy and sinks downwards, cooling the rest of the compartment. The relatively warm and light air moves upward, and this cycle continues till uniform temperature is attained.
  • Copper vessel left in the air for a long time turns green. This is due to the formation of copper carbonate when copper reacts with carbon dioxide and moisture present in the air.
  • A wick in a stove keeps burning continuously as kerosene keep on raising in the wick due to capillary action.
  • The Earth rotates on its axis from west to east. This rotation makes the Sun and the stars appear to be moving across the sky from east to west.
  • The sky appears blue because the light of the Sun is spread or scattered by the myriad dust particles in the air. In space the sky would appear black as there are no dust or air particles to scatter ′ the light.
  • Food is cooked quickly in a pressure cooker because the boiling point of water increases at high pressure. Food cooks faster at high temperature.
  • In mountainous regions, the atmospheric pressure is less than it is at sea level. Water, therefore, boils at a lower temperature (Less than and food takes more time to cook.
  • The range of long wavelength radio waves is more than that of high frequency (lower wavelength) TV waves because the lower frequency radio waves are reflected the ionosphere unlike TV waves.
  • When ice floating in a glass of water melts, the level of water remains unchanged because as a solid, ice displaces an equal volume of water.
  • A man weighs more at the poles than at the equator because the polar radius of the Earth is less than the equatorial radius hence the gravitational pull is more at the poles than at the equator.
  • Standing in double – decker buses, particularly on the upper floor, is not allowed because on toting, the center of gravity of the bus is changed and it is likely to overturn.
  • The boiling point of seawater will be, more than the boiling point of pure water because the former contains salt and other impurities.
  • An ordinary clock loses time in summer because the length of its pendulum increases, and, therefore, its time period also increases. The pendulum takes more time to complete each oscillation and thus loses time.
  • Whenever there is water loss from the body, secretion of saliva is reduced resulting in dryness of the mouth and stimulating the sensation of thirst. Intake of fluid then helps in restoring the loss of the water.
  • A swimmer just out of the river feels cold particularly if it is windy, because of the evaporation of water from his body surface. The evaporation is more on a windy day.
  • Alcohol is sometimes rubbed on the body of a person suffering from fever. As soon as it is applied on the body, it evaporates taking away some heat from the body. Since evaporations has a cooling effect, the body temperature can be reduced by rubbing alcohol.
  • Soft iron is used as an electromagnet because it remains a magnet only while the current passes through the coil around it and loses its magnetism when the current is switched off.
  • The person jumping out of a moving train is carried forward in the direction of the train because the person himself is in motion sharing the velocity of the train and will continue in its state of uniform motion unless it exercises some force to prevent it (Newton՚s first law of motion.) .
  • A lightning conductor is fixed to all buildings to protect them from the destructive effects of the lighting.
  • An electric bulb makes a bang when it is broken because there is a vacuum inside the electric bulb. When the bulb is broken air rushes in at great speed from all sides to fill the vacuum the rushing of air produces a noise generally referred to as the “bang” .
  • Glass is more elastic than rubber, because the strain produced in glass is much smaller as compared to that produced in rubber.
  • A small space is left between each set of two rails of railway line to allow for their expansion in summer.
  • A bad egg floats in water because the up- thrust produced on account of displaced water by the immersed portion of the bad egg is greater than the weight of the egg.
  • Moisture gathers on the outer surface of a glass tumbler containing cold water because the water vapors present in the air get cooled and appear as droplets of water on coming in contact with the cold surface of the glass tumbler.

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