# Call 95 - 8004 - 8004 to know about our

• Published 2014

#### Abstract

UNITS AND DIMENSIONS The digits expressing a numerical value of a quantity is called Significant Figure. If the unit of a measurement is changed, its significant figure will remain Unchanged The length is measured in metre, centimetre, etc. Some other units to measure the large distance are parsec, light year, etc. The distance covered by light in one year is called 1 Light Year [NDA 2009] Every unit can be expressed in terms of base units with the help of dimensional analysis. In dimensional equation, the power occurred on a base quantity is called dimension of given quantity in a particular [SSC CGL 2013] Base Quantity The plane angle is ratio of arc and radius with SI unit radian. Name a unit of plane angle other than radian. Degree The study of law of nature is Physics and the quantities involved in it are known as physical quantities on the basis of magnitude and direction. The physical quantities are of Two Types In which unit, sound level is measured Decibel A system of unit may be selected such that it is invariable easily available and Reproducible If work is performed on a body, its energy can be changed. This shows that there is relation between work and energy. The SI unit used for these two quantities are Joule (J) Quantities/Units/Symbols Fundamental or BaseQuantity SI Unit Symbol Length Metre m Mass Kilogram kg Time Second s Electric current Ampere A Thermoclynamic temperature Kelvin K Amount of substance Mole mol Luminous intensity Candela cd Complementary Quantity SI Unit Symbol Plane angle Radian rad Solid angle Steradian sr MOTION Acceleration is the rate of change of velocity. The negative of the acceleration is known asRetardation.For a retarding body, change in velocity is always [CDS 2010] Negative The speed or velocity at a time can be found by position line graph for a moving body. If graph is like a curve, then instantaneous speed of the body may be found as ......... on the curve. Tangent When a body is obliquely thrown from the Earth surface, it is called a Projectile. The velocity of projectile can be resolved into two components. The horizontal component of velocity is always Constant The relative speed is known as the speed of a body with respect to another body. It can differ from actual speed of the body. It two bodies are moving with same speed and in same direction, their relative speed is Zero A person jumps from an aeroplane with parachute. The graph between depth and time for the person found to be A Curve For a body moving with constant acceleration, the velocity-time graph is straight line. In case of non uniform acceleration, the graph will not be A Straight Line The motion along a circular track is known asCircular Motion.It is of two types,UniformandNon-uniform.The acceleration common to both types of circular motion, is Centripetal Acceleration Types of Motion Type Example One-dimensional Motion along at straight line, free fall of a body Two-dimensionat Circular motion, projectile motion Three-dimensional Motion of a bee, motion of dust particles in atmosphere, etc. LAWS OF MOTION For equilibrium ofabody, sum of all the forces acting on it should be zero and forces should be concurrent. In case of forces are not concurrent, the body may. Rotate Newton gave three laws of motion, according to one of them the property of body to continue in its state of rest or that of uniform motion in a straight line in the absence of external force is known as Inertia Law of inertia tells that a body tries to remain in their initial physical state, until a force acting on it. Here force should be Unbalanced A pendulum is hanging in a car deflects from vertical position when car accelerates. Here, the law of Call 95-8004-8004 to know about our Pendrive/Tablet & Android Courses

### Cite this paper

@inproceedings{2014Call9, title={Call 95 - 8004 - 8004 to know about our}, author={}, year={2014} }