# The Various Sciences, Science Laws Etc and Measurement Units

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## Various Sciences

Acoustics : The study of sound and sound waves

Agrostology : The study of grasses

Anatomy : The science of the structure study of the animal / human body learnt by dissection

Astronautics : A science dealing with space travel & space vehicles

Astronomy : The science of heavenly bodies (planets)

Biology : The science of living organisms

Botany : The science of the plant kingdom

Bryology : The study of mosses

Cardiology : A branch of medicine dealing with heart

Chemistry : The study of elements, their behaviour and laws of their combination, etc.

Cosmetology : The study of cosmetics and their use

Dactylogy : The study of fingerprints

Dietetics : The science of diet and nutrition

Endocrinology : The study of glands

Lithology : The study of the characteristics of rocks

Mycology : Concerned with fungi and fungal diseases

Nephrology : A branch of medicine dealing with kidney diseases

Oncology : Study dealing with tumours

Orology : The study of mountains

Paediatrics : A branch of medicine dealing with child diseases

Pathology : A branch of medicine that deals with etiologies, mechanisms and manifestation of diseases

Psychiatry : The study & treatment of mental & emotional disorders

Radiology : A branch of medical science dealing with the use of x-rays for diagnosis and treatment

Rheumatology : The study of small joints in human body

Seismology : The study of earthquakes & related phenomena

Theology : The study of religions

Virology : The science that deals with viruses

Zoology : A branch of biology that deals with animal life

Zymology : A study that deals with the process of fermentation.

## Science Laws Etc

Archimedes’ Principle: It states that a body, when immersed in a liquid, experiences an upward thrust equal to the weight of the liquid displaced by it.

Avogadro’s Hypothesis: It is a modification of Berzelius’ hypothesis. It states that equal volumes of all gases under similar conditions of temperature and pressure contain equal number of molecules.

Boyle’s Law: States that the volume of certain gas is inversely proportional to the pressure at a constant temperature. In other words, the product of pressure and volume remains constant provided the temperature is kept constant i.e., P x V = a constant, if T remains the same.

Charles’s Law: It states that at constant pressure all gases expand by of their volume at 0oC i.e., the volume of a given mass of gas at constant pressure is directly proportional to the absolute temperature.

Dulong and Pettit’s Law: States that the product of atomic weight and specific heat of solid elements is nearly equal to 6.4 i.e., At. wt. sp. heat = 6.4 approx.

Gay-Lussac’s Law of Combining Volumes: Gases react together in Volumes which bear simple whole number ratios to one another and also to the volumes of the products, if gaseous - all the volumes being measured under similar conditions of temperature and pressure.

Graham’s Law of Diffusion: States that the rates of diffusion of gases are inversely proportional to the square roots of their densities under similar conditions of temperature and pressure.

Law of Definite Proportions: A chemical compound is always found to be made up of the same elements combined together in the same ratio by weight.

Law of Floatation: For a body to float, the following conditions must be fulfilled: (1) the weight of the body should be equal to the weight of the water displaced. (2) The centre of gravity of the body and that of the liquid displaced should be in the same straight line.

Newton’s Law of Universal Gravitation: States that “Every portion of matter attracts or tends to approach every other portion of matter in the universe with a force proportional to the masses and inversely as the square of the distance”.

Newton’s First Law of Motion: A body continues in its state of rest or of uniform motion in a straight line unless compelled by an external force to change that state.

Newton’s Second Law of Motion: The rate of change of momentum is proportional to the impressed force and takes place in the direction of the force.

Newton’s Third Law of Motion: To every action, there is an equal and opposite reaction, e.g. Rockets, recoil of a gun.

Newton’s Law of Cooling: States that the rate of loss of heat of a hot body is directly proportional to the difference of temperature between the body and the surrounding and is independent of the nature of the body.

Ohm’s Law: States that the ratio of the potential difference between the ends of a conductor and the current flowing in the conductor is constant. e.g., for a potential difference of E volts and current/amperes, the resistance R, in Ohms is equal to E /me.

Principle of Conservation of Energy: It states that, in any system, energy cannot be created or destroyed; the sum of mass and energy remains constant.

Specific heat of substance: The quantity of heat required to raise the temperature of 1 gm. of a substance through 1C.

## Measurement Units

Angstrom: For measuring length of light waves

Barrel: For measuring liquids. One barrel is equal to 31½ gallons or 7,326.5 cubic inches

Cable: For measuring length of cables. It is about 183 m. in length

Carat: Used for measuring precious stones. It is also a measure for the purity of gold alloy

Fathom: It is used for measuring depth of water. One fathom is equal to 4 inches

Knot: For measuring speed of ships

Horse Power: Used for measuring the power of petrol or steam engine

Light Year: A light year is the distance light travels in one year at a speed of 2, 97,600 km per second

Nautical Mile: A unit of distance used in navigation - one minute of longitude measured along the equator. A Nautical Mile is approximately equal to 1853 metres

Ohm: The unit of electrical resistance of a conductor

Quintal: Metric measure of weight, 100 kilograms = 1 Quintal.