Velocity with direction Velocity of object is defined as the displacement of the body per unit time. Velocity= Displacement/time It is a vector quantity . Its SI unit is m/s & in CGS system cm/s . Acceleration. The change in velocity or speed of moving object is measured in term a physical quantity called acceleration. Definition – It definition as the change in velocity of object in unit time . It is represented as a. a =change in velocity/time interval its SI unit is m/s2 it is vector quantity Formula & Expression for Acceleration Expression Let Initial velocity of moving object =u velocity =v change in velocity = ∆V Time taken to change in velocity = =t-0 ∆t Positive Acceleration- *If V˃U then a=+ve Negative Acceleration─ * If V then a= ve (Retardation) Retardation - − ˃U If acceleration is Ve (V>U) then it is called Retardation or Deacceleration. – Graphical Distance-Time --- Presentation of Graphs between Distance travel by moving object at different time is called Motion graph. For stationary object Y distance o X time Chapter MOTION Topics Key points For Uni-form motion y d
Velocity Acceleration. Formula & Expression Retardation - Graphical Presentation of Motion with direction Velocity of object is defined as the displacement of the body per unit time. Velocity= Displacement/time It is a vector quantity . Its SI unit is m/s & in CGS system cm/s . The change in velocity or speed of moving object is measured in term a physical quantity called acceleration. Definition – It definition as the change in velocity of object in unit time . It is represented as a. a =change in velocity/time interval its SI unit is m/s2 it is vector quantity Expression for Acceleration Let Initial velocity of moving object =u velocity =v change in velocity = ∆V Time taken to change in velocity = ∆t =t-0 Positive Acceleration- *If V˃U then a=+ve Negative Acceleration─ * If V ˃U then a= − ve (Retardation) If acceleration is – Ve (V>U) then it is called Retardation or Deacceleration. Distance-Time --- Graphs between Distance travel by moving object at different time is called graph. For stationary object Y distance o X time Chapter MOTION Topics Key points For Uni-form motion y d
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